As send via E-Mail, I told the same with 24.0 and 24p having these issues. The
"sw cts/n values" patch made audio drops with 50 / 60hz much better - but I
also have to admit: 

Reverting the "sw cts/n values" patch makes 24p working flawless again.

If it is not too late for 3.12 perhaps reverting the "sw cts/n values" patch
would be an option?