I’m afraid I’ll need to jump in here as well. Read carefully as my issue seems to be two-folded:
Ever since I’ve upgraded to 4.14, I noticed the “Under-voltage detected! (0x00050005)” in my dmesg.
I’ve disconnected all USB devices except by boot disk, and have tried multiple (three!!!) different PSUs, the issue remains. This under-voltage message has been introduced in the 4.14 kernel, and it seems people aren’t that happy with it (see Under-voltage detected! (0x00050005) spams dmesg on new kernel 4.14.30-v7+ · Issue #2512 · raspberrypi/linux · GitHub). I’m still not sure if this is an actual issue with my Pi3, or something fundamentally broken.
I’m using my rPI as both mediacenter, but also as ADSB-receiver. The reason I’ve started looking into this is because after the March 5 update my so-called “mlat client server status” is showing as “clock unstable” and therefor not able to sync with other mlat-clients. I’ve never had this, therefore suspected the 4.14 kernel. Now after manually downgrading the kernel to 4.9.29-10-osmc, the clock is stable and mlat running happily, confirming my theory.
Perhaps a long stretch, but I got a hunch this could be related to the stuttering as experienced here: Playback Video - sound stuttering after March 5th Update - #108 by modul8
Just wanted to share my experience and feedback. I’d love to help and test in order to get 4.14 running as happy as 4.9. If anything is needed, let me know.