After updating my watch 4 classic to the new One UI 8 I have noticed these issues listed below. Does anyone here notice them too?
โ Wrist detection seems to be broken. Having to keep putting in pin when screen goes dark.
โ Knock knock feature won't work after device power down. For it to work it has to be toggled off then on and then re-selecting the App to associate it with. (This also affects my watch 6 after update)
โ Sleep detection not working at all. Before I had no issue and sleep recording was accurate.
@Khemikhall I have a feeling that the Sleep detection issue is related to the wrist detection issue. If it doesn't detect your wrist, it won't record any sleep.
After the update, did you wipe the device cache on the watch?
A lot of devices have bugs after that update. I have a Watch 4 Classic and still haven't received it. I believe they pulled the update to fix those bugs because you can pull it up on Sammobile.
I'm having the same issue with the sleep detection. I have checked as much as I can to try to figure it out but nothing helps. I wish they would fix it. I got tired of putting my pin in every time I wanted to look at my watch so I turned off the pin. It fixed that part but that's it
These and also the heart rate function no longer works - even when it does manage to catch a rhythm, its totally wrong. Logging a workout is a nightmare - if I select treadmill for example, it opens the step count, heart rate, or weather screens instead of launching the workout. When I can get it to launch the correct workout, it randomly stops and also the caloric burn is off by 100s of calories because it wont measure heart rate. This is seriously negatively impacting my fitness training and overall health since I can't adjust my caloric intake to match my output. If it's not resolved soon I will be switching to Garmin.
I am opening this thread to consolidate reports regarding the critical issues introduced by the stable One UI 8 (Wear OS 6) update (Build: CYK2) for the Galaxy Watch 6 and Watch 6 Classic. While the update was highly anticipated, it has caused significant regressions in basic functionality and performance.
I am specifically looking for an official update from Samsung or any information regarding the global rollout of the CZA6 stabilization patch.
Key Issues After CYK2 Update:
Broken Sleep Tracking Details: The watch records the total duration of sleep, but the granular data is completely missing. I am seeing zero data for Sleep Stages (REM, Deep, Light), Blood Oxygen (SpO2), and Heart Rate Variability (HRV). Because these metrics are missing, the Energy Score feature is broken and remains stuck on "Calculating" or "Waiting for data."
Massive Battery Drain: There is a widespread drain of approximately 10% per hour, even with Always-On Display (AOD) disabled and no active usage. System logs suggest that Google Play Services and various system wakelocks are preventing the device from entering deep sleep.
Severe UI Lag: The interface performance has significantly degraded. Frame drops and freezes are common when accessing the Quick Panel or switching between apps. The animations seem to exceed the current hardware optimization.
Information Request Regarding CZA6 Update:
Internal trackers and CheckFirm logs have identified a new test firmware build: R9xxXXU1CZA6. Reports from the South Korean market suggested that a maintenance release to fix these specific issues was scheduled to begin its rollout around January 12, 2026. However, many of us in global regions have yet to receive any notification or an official timeline.
My Questions:
Has anyone in global regions received the CZA6 (or a newer) stabilization patch yet?
Is there an official confirmation on the global release schedule for this hotfix?
Has Samsung officially acknowledged the CYK2 build as a known issue to ensure support centers prioritize software fixes?
I look forward to a swift resolution and the official release of the stabilization update for my device (SM-R930).
