EIII not sampling though VU meters show input signal

[willgregory]

Dear EIII Friends,

I experience a strange problem with my EIII rack. When I try to sample from the analog inputs, in the sample setup I can see the input signal, set the threshold, see the available memory and adjust the sampling time. But when I try arm or force sampling, the EIII is immediately jumping out of the menu and creates a sample with 0.0 seconds, like immediately terminating the sampling process.

All other EIII system functions work perfectly. Memory check is ok, Frequeny reponse loopback test is ok, I can load Soundbanks and everything plays back fine. I did not use the sampling input before as I used Alchemy to dump samples into the EIII but I wonder if I am missing something here. Has anybody experienced the same problem or has an idea what could cause such a behaviour?

Thanks for any help, Gregor

[wirefall]

Have you checked PSU/voltage?

[willgregory]

Yes, PSU and Voltages are all fine. The EIII works perfectly otherwise, memory checks are ok and it plays back samples without any problems. The sampling inputs also work, I can see the VU meter moving in the display, but the actual sampling process is not initiated, neither by arm or force sampling