It's a tricky problem because like I said the problem really doesn't
start until the machine gets 'warmed up.' So I can turn it by hand and
when it's not warmed up even run it without hearing the noise.

The problem does seem to be getting worse though. You cannot run the
machine with a full load without the noise going. In fact it only
takes 2-5 minutes now and that time seems to be getting shorter.

For what ti's worth it's a Hot Point.