Can I connect my computer audio output to the computer input (I/O) on the back of the Rotel?
No. The RJ45 computer I/O input on your Rotel product is only used for external control using third-party developed RS232 control software such as Crestron or AMX. This input is also used in the case that a software upgrade is needed for your Rotel equipment.
If your computer has analog or digital audio outputs you could connect your computer to a Rotel receiver or surround processor using one of the analog or digital inputs as you would connect any other source component such as a DVD player or CD player. Or, for even better sound quality, add a USB DAC to your system such as the RDD-1580. The RDD-1580 features a rear panel PC-USB connection that can be used to connect your computer to the system for high quality audio playback.