Cant umount degraded raid

Hello,

again i got the same problem like in this already solved thread. last months it happend from time to time, but i could solve it by doing the discribed steps again.
Clean, degraded Raid (Mirror)

but today it doesnt work, because i cant umount the raid. i get this error-message:

root@HomeServer:~# mdadm --stop /dev/md127
mdadm: Cannot get exclusive access to /dev/md127:Perhaps a running process, mounted filesystem or active volume group?

of course i tried to umount the raid before without getting a error-message - but the raid is still mounted.

even these commands dont bring up a result:

root@HomeServer:~# lsof /dev/md127
root@HomeServer:~# fuser -m /dev/md127

can you help me to get the raid unmounted?

thanks, alex!

still couldnt solve the problem. any ideas?

perfect! thank you very much!