#21 The Deep Dive Fix Files: Week Ending 23 October 2026

This is a weekly roundup of significant sports tech problems that the endurance community has encountered and, where possible, resolved. Each entry covers the issue, the affected hardware or software, and the current best fix or workaround known to the community.

Garmin Edge 1050 freezing and losing the ride log, and Varia 715 disconnecting on firmware 32.20

One Edge 1050 owner on firmware 32.20 had two freezes in a single stretch of riding. The first wiped the whole ride log. The second cut the Varia 715 signal and cost some data. The radar light also drops and reconnects often, whether you ride in a group or alone.

A factory reset after the first freeze did not stop the second. After that, the owner deleted all saved sensors, restarted the Edge, reset the Varia 715 and paired everything again. They have not ridden since, so nobody knows yet whether it holds on the road.

Another rider says beta 33.11 still has bugs but runs much better than 32.20. The original poster installed it but had not tested it on a ride, nobody else has confirmed it, and Garmin staff have not replied. Another suggestion, to give the phone app every permission it asks for, has no explanation and no reported results.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Wahoo ELEMNT ROAM 3 switching a Garmin Varia RTL515 rear light off when Auto Light is on

With Auto Light set to 1, 5 or 10 seconds, one ROAM 3 owner finds the computer turns the Varia RTL515 light off when a car approaches. The radar still spots the car and the ROAM still sounds the alert, but the rear light does not flash. The 5 second setting worked for this rider before, and both devices are on the latest firmware.

Resetting both devices and re-pairing the radar did not help. Wahoo’s support page says Auto Light set to off leaves the light in whatever mode it was last in, which keeps it on all the time. The rider does not want that because it drains the Varia battery.

A second rider with a ROAM 3 and a Varia RCT715 says Auto Light works for them after setting the light to off, triggering the flash and choosing the longest time setting, though they could not remember the exact steps. One forum user thinks the ANT+ radar profile has no auto on and off command, which could explain why third-party lights misbehave.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Suunto Run 2 optical heart rate reading far too low or spiking at rest

One Run 2 owner saw wrist heart rate match a Polar H10 chest strap within about one beat on a tempo run. On a later steady run it never rose above 130 bpm and averaged 84 at a fast pace. Their earlier Run 1 had been consistent. A second owner sees spikes to 159 bpm while sitting at a desk, against a normal resting range of 50 to 60.

A soft reset did not fix it for the second owner. A moderator suggested a soft reset, then a hard reset, then support. The first owner skipped those steps, and their next run read perfectly with nothing changed, so the cause is still unknown.

One user suspects cadence lock, where the sensor tracks step rate instead of pulse, and suggests comparing the heart rate trace with cadence. They say a textile Athletic7 strap fixed it on their Race S and Vertical. Suunto has not acknowledged a known fault or a firmware fix.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Fenix 8 overstating distance with an HRM-Pro Plus on software 23.39

A Fenix 8 owner on software 23.39 recorded 21.27 km at the Paris 20K, which has an official distance of 20.08 km. Pace looked right throughout, and the course trace in Garmin Connect measured 20.08 km, so the route was not the problem.

The owner was wearing an HRM-Pro Plus and suspects the strap is feeding distance to the watch. A Garmin reply says the strap can affect calculated distance and points to a support article on calibrating its pace and distance feature. It does not confirm a bug or promise a firmware fix.

That leaves two options. Calibrate the strap on a measured course, or turn off the HRM Pace and Distance capability in the strap’s settings so the watch relies on GPS. The owner switched it off for future races, but nobody has yet confirmed that this brings the distance back in line.

Wahoo KICKR CORE v2 dragging and rubbing with a SRAM XPLR 11-44T cassette when the thru axle is tightened

A KICKR CORE v2 owner swapped the stock Shimano cassette for a SRAM XPLR 11-44T so a gravel bike could run on the trainer. Pedalling by hand then felt stiff and rubbed. The drag vanished with the thru axle loose and came back when it was tightened.

The first reply suggested checking the cassette is seated properly and that the spacers match the SRAM cassette on the freehub, and not over-tightening the axle. The owner did not say whether that helped.

Swapping the supplied black adaptors for silver ones sold separately made no difference, but going back to the black ones cleared the problem. The owner thinks the black non-drive-side adaptor fits snugly while the silver one sits loose, but has found no root cause. Nobody else has reported it and Wahoo has not replied.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Forerunner 970 Bluetooth dropping from iPhone since software 18.32

A Forerunner 970 owner says the watch keeps losing its Bluetooth link to an iPhone running iOS 27 since software 18.32. When the drop happens, the watch disappears from the iPhone’s Bluetooth settings altogether.

Restarting the watch and force-closing the Garmin app mostly restores the connection, but it drops again after a while. The owner calls this a partial workaround, not a fix.

The thread has one reply and no Garmin staff response, so nobody else has confirmed the same fault. Other Forerunner 970 threads on 18.32 report lost sleep hours and crashes, and it is unclear whether those share a cause.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Forerunner 965 heart rate sensor dead with no green light and battery draining within a day after software 29.05

Several Forerunner 965 owners say that after software 29.05 the optical heart rate sensor stops working. The green lights stay off, wrist heart rate shows dashes, and a battery that used to last about 14 days empties in under a day. One owner installed 29.05 on 29 August and lost the sensor around 5 September.

Powering off, a factory reset, reinstalling the software from a computer and rolling back to 28.05 all left the light off. The only route that has worked is a warranty replacement. One owner says Garmin support had them factory reset the watch and film the dead sensor before approving it, and another got a refund through Amazon.

The cause is not confirmed. Sleep tracking and pool length counting also failed on affected watches, which one owner reads as a wider sensor fault, while another thinks 29.05 may not be to blame. No Garmin staff reply appears in the thread.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Enduro 3 and Fenix 8 goal reached notifications appearing with goal alerts turned off since software 22.35

Enduro 3 and Fenix 8 AMOLED owners say goal reached notifications for steps, floors and intensity minutes keep appearing with goal alerts switched off, even in focus modes. Reports start with software 22.35, and one owner says Beta 23.13B still has the fault.

Toggling the setting, restarting and a factory reset with a backup restore changed nothing. Garmin staff suggested turning off push notifications in Garmin Connect, but that only silences the phone and not the watch.

The one workaround that hides the alerts is to set the step, floor and intensity minute goals so high they are never reached. The watch still tracks all three. Garmin staff say the reports are under review and have promised emails asking for details, but no fix has been posted.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

COROS watch not syncing and iPhone app not connecting since September 16

iPhone users on COROS app versions older than 4.9.11 lost their connection after COROS renewed its standard connection certificates on 16 September 2026. The app will not open or connect and the watch will not sync. Android is not affected, and COROS says accounts and synced history are safe.

The fix is to update the app. Open the COROS page in the App Store, tap Update, then open the app and sync the watch. If no Update button shows, tap the profile icon in the top right, pull down to refresh the list, and restart the iPhone if it still does not appear. The latest app needs iOS 15 or later.

If you have workouts that have not synced, do not uninstall the app or reset the watch. COROS says to photograph them in the watch’s history widget and contact COROS Support. Updating to 4.9.11 works at any time after the 16 September date.

Garmin Forerunner 970 overnight skin temperature not syncing to Garmin Connect since the latest update

Forerunner 970 owners say the overnight skin temperature change shows on the watch but never reaches Garmin Connect since the latest update. One owner says every other metric uploads normally and that the watch syncs over Wi-Fi.

Garmin staff first suggested syncing through Garmin Express on a PC, which is the cheapest thing to try. If that fails, they recommend removing the watch completely from the Garmin Connect app and from the phone’s Bluetooth settings, then pairing it again from scratch.

Nobody in the thread has confirmed that either step worked, and it is not clear whether a re-pair helps people who sync over Wi-Fi.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Fenix 8 Bluetooth drops, screen brightness faults and broken apps after software 23.31

Fenix 8 owners on software 23.31 report Bluetooth problems, screen brightness faults, disconnections and broken apps. The original poster says Garmin has not reproduced the faults and is asking for a patch.

One owner fixed it by reinstalling the software on the watch. Go to Settings, System, About, press the Light button eight times, then choose the reinstall option. They did it twice and say the strange behaviour stopped. Another owner reports no problems on 23.32, with better battery life and more reliable satellite lock.

Going back to 22.x is possible but erases all data, so back up first. Users disagree on whether to target 22.44 or 22.38. Garmin has posted no patch or official response.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Suunto oCycler recording 0.00 km distance and 1 rpm average cadence on an indoor bike ride after sync

oCycler is a SuuntoPlus app that connects to an indoor bike and records live data in the workout summary. Several users see correct power and cadence on the watch during the ride, then zero distance after sync. A Suunto Race owner with a Zwift Hub also got an average cadence of 1 rpm.

One user edits the ride afterwards and adds the distance by hand. The developer has asked affected users to email the .fit file and a recording of their bike’s protocol, and pointed to the QZ app as another route.

SuuntoPlus apps cannot overwrite standard power or cadence fields, so training stress stays heart rate based. Suunto watches read trainers that broadcast cycling power natively, while spin bikes often send only estimated power.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Suunto Run 2 24/7 optical heart rate sensor staying on constantly or stopping outside workouts

Run 2 owners with 24/7 heart rate turned on describe two opposite behaviours. In one, the green lights flash while the heart rate widget is open and stop when you leave it, so the widget shows an old reading. In the other, the lights stay on constantly and the battery drains faster, with one estimate of about 10 percent over eight hours.

A soft restart has worked for several users. Hold the upper button for 12 seconds until the watch reboots. One says it only helps temporarily, and another says the fault often returns after charging or an activity, so you may need to repeat it. A factory reset did not help the one user who tried it.

Users disagree on how often the Run 2 should sample, and no Suunto staff have answered. Lights that flash and then stop may be normal, while lights that never switch off together with fast battery loss point to a fault.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Fenix 8 AMOLED Iron Grit watch face only half drawing after waking from idle on 23.39 and 23.40

After the watch has been idle, a wrist raise or a press of the Light button draws only the top part of the stock Iron Grit face. The rest fills in about half a second later. If the watch was used recently, the wake-up is smooth. The original poster first saw it on 22.44 and still sees it on 23.39 and 23.40.

Other stock faces are not affected, and an owner running a third-party face based on Iron Grit had no problems, so switching faces is the cleanest workaround so far. Switching faces and back, changing the language or restarting clears it for a few hours or a day. Resets and a factory reset did not fix it.

Garmin staff said they could not reproduce the issue and recommended a reset and contacting Product Support if it continues. No cause or fix is confirmed.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Fenix 8 Pro crashing with a blue triangle when saving an activity on 23.39, and the run missing from weekly mileage

A Fenix 8 Pro owner on 23.39 says the watch crashed while saving an activity and then showed a blue triangle for a couple of minutes. The activity is in the watch log but is not counted in the weekly mileage total.

Garmin staff offered three steps. Power cycle the watch. If the watch was set up from a backup restored from an older device, reset it and set it up from scratch. If the crash only began after the latest update, reinstall the software through Watch Settings, System, About, pressing the Light button about eight times and choosing Reinstall Software Version.

The original poster has not reported back, and nobody has confirmed that any of the three steps stops the crash.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Edge 850 temperature reading 3 to 20 degrees too high while the weather widget is correct

Edge 850 owners say the temperature data field and top bar read at least 3C too high in one thread and about 20C too high in another, while the weather widget shows the right figure. One rider says Garmin has not fixed it in nearly a year.

The two numbers come from different places. The widget uses weather data delivered through the Garmin Connect app on your phone. The data field reads a sensor inside the Edge, so it shows the temperature of the device itself. An Edge sitting on a desk will read about 25C whatever the weather.

One rider uses an offset data field to correct the reading, though he says it is not perfect. Another suggests checking the weather details on the ride in the Garmin Connect browser version. Garmin has not released a system-level offset and only points to Product Support.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Edge 850 showing Shimano Di2 gear data during the ride but not in Garmin Connect activity analysis

A rider with a Shimano Deore XT Di2 drivetrain finds the Edge 850 shows gear data during a ride but offers no way to analyse it afterwards, while SRAM gear data can be analysed. Another owner on firmware 32.20 sees the same behaviour.

The data is recorded, and Garmin Connect shows a basic version. Open the saved ride, go to Overview and scroll down to Electronic Shifting Data. It lists time spent in each sprocket but has no charts.

For more detail, export the .fit file and load it into Intervals.icu or WKO5, which both read the shifting data. One user reports that the SRAM AXS web app also produces shifting summaries for Shimano Di2 rides, but that comes from a single reply and is untested.

Suunto Vertical 2 logging evening sofa time as sleep and skewing morning sleep data

A Vertical 2 Titanium owner says the watch logs evening relaxation as sleep. Sitting on the sofa from about 6:30 pm was recorded as sleep, which skewed the next morning’s data. A Race 2 owner says a nap at the hairdresser was detected the same way.

Heart rate settings are the fix that appears most often. One owner lowered the minimum heart rate setting until watching TV no longer triggered sleep, though naps then went undetected. Another lowered the Rest HR setting and the problem went away. A Vertical 2 owner says setting a usual bedtime together with a minimum heart rate gives accurate tracking.

A Suunto community manager suggested adjusting the sleep time to match a variable bedtime, but the original poster already had one set. One user on a newer watch says those models use automatic Do Not Disturb timing instead, and their sleep times then matched an Oura ring within minutes.

Garmin Fenix 8 touchscreen jumping back to the watch face on every tap after software 23.39

Fenix 8 owners on 23.39 describe a touchscreen that sends the watch back to the watch face on almost every touch. One says it is usable only with the touchscreen disabled, and others report the same fault after each update for months, clearing for about a day and returning.

Garmin staff say engineers are investigating and suggest calibrating the buttons, power cycling the watch and syncing through Garmin Express. No lasting result has been reported. One user found two pending updates in Garmin Connect that had not installed after an automatic update, and installing them cleared the jumping, so check the phone app for a stuck update first.

The practical fallback is to turn the touchscreen off and run the watch on buttons alone, which stops accidental screen changes during activities. One user was offered a paid exchange for a recertified unit, and Garmin could not promise it would be unaffected.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

Garmin Edge 1050 losing a Bosch eBike as a sensor after beta firmware 33.12

Several Edge 1050 owners say a Bosch eBike disappears from the sensor list after updating to firmware 33.12, which is a beta build. The bike still shows in the Bosch Flow app and Flow can see the Edge, but the Edge shows no data and the pairing spinner never completes.

Re-pairing does not help. One rider removed the Edge from the system and added it again, and another removed everything and restarted the phone, the bike and the Edge. Neither got the bike back.

The only workaround is to go back to the stable 32.20 release, where one user says Bosch pairing works, but nobody has tested the rollback on an affected unit. Bosch pairing worked all summer on an earlier beta, so the fault looks specific to 33.12. Garmin staff have not replied.

This issue remains unresolved — if you have encountered it and found a fix, the discussion is open on r/the5krunner.

More from last week’s Fix Files roundup.

Browse every issue in the archive at the Deep Dive Fix Files hub.

Last Updated on 23 October 2026 by tfk the5krunner