It is a while since there is no more message in this topic, but I experience the same problem (one more...)
I do not have any aswer to this, but it seems to me the following : when you look at supported SCSI commands for the Ultraplex40max using SandraSisoft, it seems it does not support "Terminate I/O", whereas my Pioneer DVD304S does.
When you look at "Terminate I/O", the standard says :
" The TERMINATE I/O PROCESS message is sent from the initiator to the target to terminate the current I/O process without corrupting the medium. "
and also :
" ... The TERMINATE I/O PROCESS message provides a means for the initiator to request the target to reduce the transfer length of the current command to the amount that has already been transferred. The initiator can use the sense data to determine the actual number of bytes or blocks that have been transferred. This message is normally used by the initiator to stop a lengthy read, write, or verify operation when a higher-priority command is available to be executed. It is up to the initiator to complete the terminated command at a later time, if required. "
Does it mean Plextor did not implement properly this SCSI-2 command ??