Getting error message as "media manager killed by signal(82)"

Hello,

We are facing issue while taking backup of VM on VTL. We have configured mhVTL on media server. Getting error message as "media manager killed by signal(82)". We are successfully able to take backup on disk but not on VTL.

Setup details :

Netbackup version : 7.5

Master server : Windows 2008 R2

Please see below logs for details :

12/19/2013 5:46:58 PM - Info nbjm(pid=2704) starting backup job (jobid=1592) for client tsm-vm6, policy Windows_Testcollector_1month_Vmware, schedule full_1month 
12/19/2013 5:46:58 PM - estimated 0 Kbytes needed
12/19/2013 5:46:58 PM - Info nbjm(pid=2704) started backup (backupid=tsm-vm6_1387455418) job for client tsm-vm6, policy Windows_Testcollector_1month_Vmware, schedule full_1month on storage unit tsm-vm8-hcart2-robot-tld-2
12/19/2013 5:47:00 PM - started process bpbrm (27451)
12/19/2013 5:47:00 PM - Info bpbrm(pid=27451) tsm-vm6 is the host to backup data from    
12/19/2013 5:47:00 PM - Info bpbrm(pid=27451) reading file list from client       
12/19/2013 5:47:00 PM - Info bpbrm(pid=27451) starting bpbkar on client        
12/19/2013 5:47:03 PM - connecting
12/19/2013 5:47:03 PM - connected; connect time: 00:00:00
12/19/2013 5:47:11 PM - Info bpbkar(pid=3192) Backup started          
12/19/2013 5:47:11 PM - Info bpbrm(pid=27451) bptm pid: 27454         
12/19/2013 5:47:11 PM - Info bpbkar(pid=3192) CONTINUE BACKUP received.         
12/19/2013 5:47:11 PM - Info bptm(pid=27454) start           
12/19/2013 5:47:11 PM - Info bptm(pid=27454) using 65536 data buffer size       
12/19/2013 5:47:11 PM - Info bptm(pid=27454) using 30 data buffers        
12/19/2013 5:47:12 PM - Info bptm(pid=27454) start backup          
12/19/2013 5:47:12 PM - Info bptm(pid=27454) backup child process is pid 27463      
12/19/2013 5:47:12 PM - Info bptm(pid=27454) Waiting for mount of media id B00000 (copy 1) on server tsm-vm8.
12/19/2013 5:47:14 PM - Error bptm(pid=27454) media manager terminated during mount of media id B00000, possible media mount timeout
12/19/2013 5:47:15 PM - mounting B00000
12/19/2013 5:47:16 PM - Error bptm(pid=27454) media manager terminated by parent process      
12/19/2013 5:47:33 PM - Critical bpbrm(pid=27451) unexpected termination of client tsm-vm6       
12/19/2013 5:47:34 PM - Info bpbkar(pid=0) done. status: 82: media manager killed by signal    
12/19/2013 5:47:37 PM - end writing
media manager killed by signal(82)

Please let us know the solution to resolve this issue.