Device Drive3 is disabled and will not be used

Hello.

I have DP 8 with patch BDL801

My jobs fails because drives is disabled. I change it to enable, but next days the same problem.

I test it My MSL60606 with 4 drives with HP Library and Tape Tools and all test is ok.

DP disabled drvies random. any idea??

Thank

Report:

[Warning] From: BSM@server.domain.es "Win_Incr" Time: 28/05/2014 22:00:06
Device Drive3 is disabled and will not be used.

[Warning] From: BSM@server.domain.es "Win_Incr" Time: 28/05/2014 22:00:07
[61:2013] Some of the backup devices are occupied. Session is waiting
for all the devices to get free.

[Critical] From: BSM@server.domain.es "Win_Incr" Time: 28/05/2014 23:30:37
[61:2015] Timeout waiting for the devices to get free.
The session will terminate.

[Critical] From: BSM@server.domain.es "Win_Incr" Time: 28/05/2014 23:31:13
None of the Disk Agents completed successfully.
Session has failed.