Garmin, Suunto, COROS Firmware Bugs: July 2026 Tracker

Three weeks of firmware chaos hit endurance athletes in July 2026. From Garmin Forerunner 970 pace dropping to zero mid-run to Suunto Race 2 update loops that brick your pre-race prep, the bug reports piling up across The5kRunner's Fix Files issues 7 and 8 paint a messy picture. This is what broke, who it affects, and what you can actually do about it right now.

Garmin: The Widest Blast Radius

Garmin took the most hits across both reporting weeks, which is not surprising given the sheer number of active firmware branches it maintains simultaneously. Fenix 8 AMOLED units running version 21.39 are crashing outright, and version 22.35 introduced random reboots plus lost step counts, two metrics that matter if you are tracking daily load or Hyrox prep volume. The Forerunner 970 got hit twice: elevation and HRV data corruption in the week ending July 11, then pace dropping to zero during active runs in the week ending July 24. That second bug is serious. A zeroed pace field mid-interval session destroys your auto-lap splits and corrupts any training load calculation the watch feeds into its recovery advisor. The Forerunner 570 is also stuck in a boot loop for some users, which is a hard brick scenario until Garmin pushes a fix.

Edge cycling computers fared no better. The Edge 1050 accumulated five distinct faults across the two weeks: Wi-Fi dropping, sensors failing to reconnect, ClimbPro misfiring, a map data field freeze, and TopoActive layer lockups. The Edge 850 has a particularly nasty one where loading a course triggers a boot loop, and separately loses GPS lock while in standby. Losing GPS lock on standby matters for triathletes who rack their bikes and expect a fast satellite acquisition in T1. The Edge 1040 is just slow to refresh maps, which is annoying rather than critical, but still a regression from earlier firmware. For context on what Garmin was trying to add before these regressions landed, our earlier look at the [Garmin Q2 2026 firmware updates](/en/articles/garmin-q2-2026-firmware-six-watch-features-two-edge-updates-explained-2026-06-06) shows the feature ambition that preceded these stability problems.

Suunto and COROS: Smaller Footprint, Real Problems

Suunto's bug list is shorter but the update-looping issue affecting both the Vertical 2 and Race 2 is a high-severity problem. An update loop means the watch repeatedly attempts and fails to complete a firmware install, leaving the device in a degraded state. If you are a trail runner relying on the Vertical 2's barometric altimeter for elevation gain on a race course, a stuck update the night before an event is genuinely damaging. The Suunto 9 Baro and 9 Peak Pro entries from week 7 flagged map, distance, and route errors alongside vibration alert failures. Vibration alerts are how most athletes catch interval cues without looking at the screen. Losing them during a swim-to-bike transition or a track session is a usability regression that erases meaningful training value. The light-mode map label readability issue on firmware 2.56.18 sounds minor but becomes a safety concern on technical descents where you glance at navigation for half a second.

COROS got one entry: Pace 3 dial failures. The Pace 3 sits at roughly 229 USD and competes directly with the Garmin Forerunner 265. A dial that stops responding means you cannot scroll through your training data or navigate menus, which makes post-workout review and settings changes impossible without a phone. COROS's software track record has generally been cleaner than Garmin's given its smaller feature surface area, so this is an outlier rather than a pattern. Wahoo SYSTM on Windows also appeared in week 7's list, though that is a desktop app fault rather than a wearable issue and sits outside the core scope here.

The Garmin metronome and touchscreen brightness faults from week 7 deserve a mention for runners. The metronome is a cadence coaching tool baked into Garmin's running dynamics suite. If it fires incorrectly or stops entirely, athletes using it to hit a target of 170 to 180 steps per minute during threshold runs lose a real-time cue they have trained their body to respond to. Brightness bugs on AMOLED screens like the Fenix 8 and Venu 4 are not just cosmetic. Optical PPG heart rate sensors on the wrist depend on consistent light management from the device; screen behavior and sensor behavior are separate systems, but a crashing display layer can cause the watch to suspend background sensor polling, which breaks continuous heart rate and HRV data streams.

What Is Actually Missing From These Reports

The Fix Files format from The5kRunner gives you fault identification and workarounds, which is valuable. What it cannot give you is Garmin's internal timeline for patches, and that is the gap that frustrates athletes mid-training-block. There is no public commitment from Garmin on when 22.35 reboots will be resolved on Fenix 8, no ETA on the Forerunner 970 pace-zero fix. Suunto has been equally quiet on the Vertical 2 loop. For athletes comparing platforms right now, Polar's Vantage V3 and Pacer Pro have had a quieter July in terms of critical firmware regressions, though Polar's feature velocity is slower. COROS Pace 3 and Apex 2 Pro users outside the dial fault are mostly unaffected this cycle. Whoop 5.0 runs a closed hardware-software stack with no user-installable firmware and avoids this class of problem entirely, though it also gives you zero GPS and no display. Apple Watch Ultra 3 under watchOS 27 has its own sport feature evolution tracked separately at [this watchOS 27 breakdown](/en/articles/watchos-27-sport-and-health-features-everything-endurance-athletes-need-to-know-2026-06-19), but it has not appeared in any critical bug roundup this month.

If you are in an active race build right now, the safest immediate action is to delay any firmware update on Fenix 8, Forerunner 970, Forerunner 570, Edge 850, and Edge 1050 until Garmin issues a follow-up patch. Stay on your current version. For Suunto Vertical 2 and Race 2 owners, hold on the 2.56.18 update if you have not yet installed it and the loop issue is unresolved. Check the5krunner's Fix Files weekly for workaround updates as patches land. These are not permanent platform failures, but July 2026 is a rough month to be running the latest firmware on a Garmin device.