Oppo 105 stutter

I have an Oppo 105 ca. 2012 and it's been working great all these years, except for the occasional need to reboot.

Lately I'm seeing something happening more frequently and I'm wondering what I can do. I'll be watching video and it will badly stutter to the point where the DAC can't decode much audio at all, and the picture gets very jerky., pausing more than playing. Reboot has fixed it so far, but today it happened two times in quick succession. I decided to keep it powered off for a while and try again later. So far it's not doing it. It's not particularly warm here, but I do have a Pass INT-150 sitting lower and to the right in free air. The Oppo has decent air flow.

I'd like a 4K setup but Oppo isn't making them anymore, so my question is twofold: 1) what can I do about the stutter issue and 2) what's a good replacement option where my main requirements are HDMI switching, SPDIF coax out to a DAC, and 4K support?

Thanks,
Dave