Try running a bad block scan on all audio drives. If one of the drives is developing bad blocks it may be attempting to spare them out on the fly, which could cause timeout errors. If this is the case, a low-level format may fix the problem, or the drive may need to be replaced. If this is a SCSI problem, and you have an Adaptec card, you may be able to solve it by disabling Ultra transfers in the Adaptec PowerDomain control panel. Ultra transfers are very finicky about cable length and termination. If your total cable length (including the cabling inside of the drive enclosures, which can be up to 12" per enclosure) exceeds 1.5 meters, you can get all kinds of SCSI bus problems when in Ultra mode, including random hangs -- which might trigger -9073 errors. You should also make sure you are using active termination (active terminators can be identified by their green LEDs). Try removing the FWB extension if it is active. The FWB extension constantly polls the SCSI bus to see if there are any removable devices that need to be mounted. This would add to the activity on the SCSI bus and could impact real-time operations such as audio or video playback. If you have any doubts about the quality of your cabling or termination, then you might want to check out Granite Digital at www.scsipro.com