ZeroHour, TY for sending me the Beta firmware. Unfortunately, our offline issues seem to have increased in frequency from 1-2/day to about every hour, so I'm going to revert back to the newest firmware listed on HP's site. After the Beta firmware failed to fix the issue for us, I also tried the suggestions to disable TCP/IP(v6), disable SNMPv1/v2, uncheck Multicast IPv4 and change connection timeout to 5. I also updated all the PCs to the newest PCL6 print driver, v. 61.093.02.77.
Since this seems to be working for others, I thought I'd clarify something you said in the PM you sent me. You had said that you didnt notice a firmware version change if your running the latest firmware prior to installing the BETA. I can verify that the Firmware version remains at 37.12.IR6508, but I did notice that the Firmware Date Code (from the Device Config Page) changed from 20101025 to 20100308. This way users can verify if the firmware installed.
TY for your efforts!