Thank you, Mike.

Yes, by specification you can record 8 tracks at one
time (the reason why a drummer needs something like that).

Reformatting the partition did not give any error messages,
but did not solve the problem either. I tried it several
times already.

News!
=====
The latest status is now that it starts recording
as before, but after a short time (1-2 minutes)
the system does a real crash and the display shows
only "Error Code 02".

Perhaps I could reformat the whole harddisk, but I don't
expect anything from this. As I have now unplugged my
recording setup and sent an email to the reseller, I will
wait and see what next week will bring.

PC