Hi,
I did two runs and noticed that HR locked several time on both as you can see in the picture. It seems that HR locks for some seconds in a value then it resumes spiking lowly or highly. I run with chest strap.

Hi,
I did two runs and noticed that HR locked several time on both as you can see in the picture. It seems that HR locks for some seconds in a value then it resumes spiking lowly or highly. I run with chest strap.

Thanks for the info. Just needed to include that in the troubleshooting in case anyone has any other suggestions. Battery replacement usually comes up as a possibility. If it's like the Garmin straps, they're usually a CR2032 battery. Easy to replace. At least you could then rule that out as the issue.
I don't think that is normally necessary. I have a Garmin HRM-Run it will sometimes act strange like this if it gets excessively wet from sweat or rain. In that case I take the cover off and let it sit for a week to make sure the insides are completely dry before the next use. I just use a different strap during that time.