Can multiple hung bpbkar32.exe processes cause a backup to fail 13?

We have a backup that is failing exit status 13, and when I check the client, everything looks ok except for a multitude of bpbkar32.exe processes that are running even after the backup has failed and is no longer running.  Any attempt to kill these processes is fruitless, as there are no windows utilities available to us that will kill them (pskill, process explorer, etc does not kill them).  I'm afraid the only recourse we have is to reboot, and I was just wondering if it is indeed these hung processes that is causing issues with my backup.  Right now the only thing in terms of logs I've been able to gather is what is available from the detailed status window in the activity monitor.  When I get the go-ahead I'm going to enable bpbkar and bpcd logging, but for right now, here's what I've got:

01/21/2010 19:25:06 - Error bpbrm (pid=15198) socket read failed: errno = 62 - Timer expired

Which I know pretty much means something took too long to respond.  Could the hung processes be what is causing this delay?

Thanks