Garmin, Suunto, COROS Firmware Bugs: July 2026 Roundup

The past three weeks of sports tech firmware have been rough. Between late June and mid-July 2026, trackers covering Garmin, Suunto, COROS, Wahoo, and Hammerhead logged over 50 documented faults across watches and cycling computers , and that's before counting the feature updates that shipped alongside them.

Garmin: The Biggest Bug Surface

Garmin carries the longest bug list by volume, which is partly a function of market share. The Forerunner 970 drew the most complaints: elevation data errors, sleep tracking failures, HRV status dropping out, a metronome that misfires, and touchscreen responsiveness issues. That's five distinct sensor or software failures on one device. HRV is derived from the optical PPG sensor on the wrist, so any firmware interference with that read pipeline corrupts recovery data downstream , bad news if you're pacing a training block around readiness scores. The Fenix 8 added pace freezing at 0:00, a fault that renders live run data useless mid-session.

The Edge cycling computer lineup fared worse. The Edge 1050, 1040, 850, 840, and 540 all showed up in the fix files with firmware crashes, reboot loops, ClimbPro gradient miscalculations, and navigation bugs. ClimbPro uses the barometric altimeter , air pressure converted to elevation , so gradient errors there suggest the firmware is misreading or misprocessing pressure delta. The Varia RTL515 radar pairing failure and eTap electronic groupset dropouts on the Edge 850 and 840 are connectivity bugs, not sensor issues, but they break real-world rides. The Enduro 3 sleep loop is a separate headache: the watch gets stuck cycling through sleep detection, draining battery without logging useful data.

For context, the [Garmin Q2 2026 firmware update](/en/articles/garmin-q2-2026-update-six-new-watch-features-reviewed-2026-06-14) shipped six new watch features in June. That's a fast release cadence. Fast releases and long bug tails tend to travel together.

Suunto: Vertical 2 and Race 2 Both Affected

Suunto's Vertical 2 showed two serious problems: a black screen fault that locks the display and a battery reporting error that gives false readings. The black screen issue is particularly disruptive for trail runners and ultra athletes who depend on the Vertical 2's mapping during long mountain efforts. Battery misreporting is a firmware-level calibration problem , the actual energy state of the cell and the reported percentage diverge, which means you might get a low-battery warning mid-race or, worse, no warning at all.

The Race 2 had sticky notifications that refuse to clear, power meter dropouts during rides, and backlight activation failures. Power meter data on the Race 2 comes via ANT+ or Bluetooth from an external crank or pedal-based strain gauge , the watch itself isn't generating that number. So the dropout fault likely sits in the wireless protocol handler rather than sensor physics. The Suunto 9 Baro and 9 Peak Pro added map rendering, distance tracking, route calculation, and vibration alert problems to the pile.

COROS and Wahoo Entries

The COROS Pace 3 reported dial failures , the watch face dial input stops responding, which disrupts navigation through menus and workout controls. This is a known weak point in firmware that handles capacitive or physical input, and it showed up in the week-ending July 17 fix files. COROS has been aggressive on firmware iterations through 2026, with [feature updates shipping across multiple devices in the week ending July 11](/en/articles/amazfit-q3-2026-software-roadmap-19-devices-four-key-features-2026-06-18). Speed of iteration, again, creates regression risk.

Wahoo appeared twice: an ELEMNT ROAM average power calculation fault in late June, and WAHOO SYSTM on Windows crashing in mid-July. The average power error on the ROAM affects cyclists who use normalized or average power for interval pacing , if the number is wrong, the session analysis is wrong. SYSTM crashing on Windows is a desktop training platform issue rather than a wearable hardware fault, but it affects structured training workflows for Hyrox and cycling athletes who build their plans on that platform.

What's Missing From These Reports

The fix file summaries from The5kRunner don't always confirm patch status , some entries list workarounds rather than confirmed firmware resolutions. That's a real gap. Athletes need to know whether a bug has a shipping fix or just a community workaround like resetting the device or reinstalling firmware. The Forerunner 570 strength workout button lockup, for instance, affects CrossFitters and Hyrox athletes logging gym sessions, and a soft-reset workaround is not a real solution for someone mid-WOD.

There's also no consolidated firmware version numbering in the summaries, which makes it hard to know if you're already on the affected build or have already patched past it. Garmin's own changelog pages help, but cross-referencing is manual work. For athletes managing multiple devices , a Garmin watch, an Edge head unit, and a Wahoo SYSTM plan , the cognitive load of tracking fixes across three ecosystems is real.

Bottom line: if you're on a Forerunner 970, Fenix 8, Suunto Vertical 2, or Edge 1050 right now, check your firmware version against the reported fault builds before your next key session. The Garmin Edge bugs in particular can compromise navigation and pacing data on race-day rides. COROS Pace 3 users hitting dial failures should check for a patch before a race week. Suunto Vertical 2 users on long mountain efforts should verify battery reporting accuracy manually by charging to 100% and monitoring drain rate. The feature updates are real and worth having , but in July 2026, the stability cost is visible.