Krups EA8250 Piston WIll Not Stay Down

I have an EA8250 with 10,000+ coffee cycles. Needless to say I've taken it apart and put it back together many times to fix things and replace components. I can't seem to figure out this latest issue, the piston doesn't stay down while brewing. I replaced the flowmeter based on another thread here and that didn't help. Also, every few cycles the puck stays in the chamber and the machine runs an "automatic maintenance" cycle.

Here is a video of what it is doing: Video

Any idea what is wrong? I'm not sure what to replace next.

Thanks in advance.

Trying this link again

I actually have almost the same problem. With me, the piston moves up a bit more and the coffee then runs directly over. Have you been able to solve the problem?