FR965 multiple BT devices

I have owned my FR965 for a year now. For the most part, it's awesome. I use it along with HRM PRO chest strap and I have never had issues.

Welllll, until recently. I connected my Samsung Buds to my FR965 so I can listen to music (YouTube music) without carrying my phone. Now I feel my metrics that the HRM PRO collects are messed up. Of course my cadence and HR are way off, but other metrics like GCT balance are not present.

To me it seems like the HRM PRO is having connectivity issues ORRRR there is some interference. Has anyone experienced the same? Any fixes for this?

Thanks!