BRBACKUP Failes: Physical End of tape has been reached

Dear Experts,

I am taking online/offline backup with HP ultrium LTO4 drive on 1.6TB tape.

My database is oracle 11.0.2 running on windows having 1.4TB size.

from last 1 year it was running fine. but few days back BRBACKUP failed after 50% with error as "Physical End of tape has been reached"

in init<sid>.sap file tape_size=1600 is already set.

i tried taking backup on different tapes but same issue is occuring.

I have attached init<sid>.sap file.

Kindly take look and suggest something.

Thanks in advance

Sumit Jha