Ah! This has been happening to mine, and started a few weeks ago too. I first noticed it when sending voice notes on Whatsapp - the recording would just stop itself without any interference from me. I can actually verify that this is constantly occurring every 5-6 minutes because the longest recordings I have been able to do at a time are this long, right after it has done the weird refresh. The other symptoms I had were:
It doesn't seem to interfere with audio at all, because I can listen to Spotify, and calls are not interrupted, but it is extremely irritating. It started to happen after an update, so I patiently waited until there was another update thinking that the next one released would fix this bug. I got the newest update, and the issue is still happening!
I've noticed a lot of bugs in recent updates and I'm really not impressed at this stage. They will probably eventually fix it with another update, but it's a very poor user experience.
Exactly the same thing happening on my 10+ this morning after upgrading yesterday.