Bizarre render problems in v23.3 (and v23.2.1)

I'm getting random dropouts of layers while rendering in the latest update. Layers will disappear for a frame and pop back on the next.

What's strange is that I went back a version to 23.2.1 and the randomness has gone away, but I'll have layers with frames that are out of sequence, like 1, 2, 4, 3, 5.

Any help or advice is appreciated otherwise I can't show anything to clients.