Error 13099 retrieving data from tape

I'm trying to migrate/copy 4TB of data from our Diskxtender system to a new storage array, but am encountering an error with a some of the files as follows:

"13099 Severe tapesrvr servername:7780 sendflcon.c 242
Capability requested for stage insert long hex id here
does not match capability insert long hex id here
found on tape tapeID at block blockID
Contact your DiskXtender vendor.

Does anyone have an idea what may be causing this? I've tried to trigger the same data to be staged into cache multiple times by reissuing the copy command, and each time DX does issue a mount request and mount the the tape in question, but then throws the error above.

Most of the data is staging and copying just fine, but a small percentage (2% - 5%) seems to be affected by this issue.

Thanks in advance for any feedback!

Kerry