Suunto smart heart rate strap freezing after ~30 minutes (Tried battery replacements & cleaning)

[Apor Szabó]

Hi everyone,

I’m reaching out to see if anyone has experienced a similar issue or has any advice.

I’ve had my Suunto heart rate strap for about 3 months now, and it has been working great until this past week, when it started acting really strangely.

The issue:
Every time I go out for a session, everything works perfectly for the first 30 minutes. After that, the heart rate data suddenly freezes/gets stuck on a single value and doesn’t change at all for the rest of the workout, no matter my effort level.

What I’ve tried so far:

Replaced the battery 3 times already to rule out a dying power source.

Next on my list is to thoroughly clean the snap connectors and contacts using a soft toothbrush.

Has anyone run into this exact “freezes after 30 minutes” behavior? Could it be a hardware failure, an electrode/strap degradation issue, or something else entirely?

I’ve attached some photos of the strap itself and screenshots of the data flatlining/freezing during a workout below.

Any tips or troubleshooting steps would be greatly appreciated!

Thanks,!

[elbee]

@Apor-Szabó

Could be the quite common problem where the watch looses connection with a bluetooth device and fails te reconnect.

There is no solution for that problem. Suunto should solve it but I don’t have the impression they are very active looking into it.