Do I need a switch if all network devices are for audio?

The advice here is to segregate the audio components from other network devices by using a dedicated switch.

Am I to assume that the switch is not necessary if there aren't any other devices wired to the network?

Everything else here uses wireless to connect to the router and the only wired items are the music server and NDX. I do have a Netgear switch sitting here unused from when everyone used to have wired connections but I can't really see any point in introducing it back into the network.