RMAN Validation consistently failing with "allocation failed"

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channel ORA_SBT_TAPE_1: starting validation of archived log backup set
channel ORA_SBT_TAPE_1: reading from backup piece 0ppe4d0p_1_1
RMAN-00571: ===========================================================
RMAN-00569: =============== ERROR MESSAGE STACK FOLLOWS ===============
RMAN-00571: ===========================================================
RMAN-03009: failure of validate command on ORA_SBT_TAPE_8 channel at 07/24/2014 02:13:05
ORA-19870: error while restoring backup piece c-2068283923-20140723-03
ORA-19507: failed to retrieve sequential file, handle="c-2068283923-20140723-03", parms=""
ORA-27029: skgfrtrv: sbtrestore returned error
ORA-19511: Error received from media manager layer, error text:
   Failed to open backup file for restore.

 

hcbi01:/usr/openv/netbackup/logs/user_ops/dbext/logs:higgsdv1> cat 42074202.0.1406182382
Restore started Thu Jul 24 02:13:02 2014

 

02:13:04 INF - Server status = 10
02:13:07 (6258200.xxx) INF - Status = allocation failed.

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From netbackup activity monitor

 

7/24/2014 2:13:40 AM - begin Restore
7/24/2014 2:13:43 AM - end Restore; elapsed time: 00:00:03
allocation failed(10)

 

I have applied this TN: http://www.symantec.com/business/support/index?page=content&id=TECH76719

 

But still failing after running successfully for few days.

 

Please help!