I don't have PiPifier nor am I running any Intel processes, yet I have the issue. The reason so many of us think we've found the solution is because it's so difficult to reproduce and unpredictable as to the next time it'll happen, so the issue "goes away" but it just means it doesn't happen for a period after a "phantom solution".
I installed eqMac and the problem went away. It even enables me to reproduce the issue on demand by fiddling with the bass. This seems to happen when there's a sudden change in bass so it makes sense. eqMac may be softening those transitions or keeping the bass stable or below a certain threshold that it suppresses it.
"Fixed" for now, but the underlying issue is still there, just being masked by a third party app. I'm glad to hear from some people that Apple is at least aware of this, which means they'll figure it out a lot better than us throwing stuff at the wall. I spent $6000 on this machine and if/when Apple eventually fixes the issue, I'll still have spent the entire lifetime of having this Mac dealing with unusable audio. If there's ever a class action on this, I'm going to feel 100% justified in taking back any money I can.