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.
RA-1070 | RA-1520 | RC-1082 | RC-1090 | RC-1580 | RCX-1500 | RSP-1066 | RSP-1068 | RSP-1069 | RSP-1098 | RSP-1570 | RSP-1572 | RSX-1055 | RSX-1056 | RSX-1057 | RSX-1058 | RSX-1065 | RSX-1067 | RSX-1550 | RSX-1560 | RSX-1562 | RX-1050 | RX-1052