Wonder if it's a Linux kernel scheduling issue? Like you're in some sort of power saving mode in the profile?
I thought of this mostly because you said that it fixes itself and OBS is there. OBS is a decently intensive application so the power profile might increase the clock of the CPU when OBS is running
Opening a terminal and using a command to watch the CPU frequency of each individual core might be an idea to see if this is the case.
Though I also could be completely wrong