Dedicated Sooloos audio endpoints are only 10/100 apparently to reduce chance of high frequency noise.

What switch was it - was a it a basic unmanaged switch or was it a smart/managed switch? The latter often need configuring to work better with Sooloos so its best to go as dumb a switch as possible.

Meridian owner since 1992
Prime & PSU, Focal Elear headphones, Roon (ROCK 8Gi5 NUC), Explorer 1 & 2, F80. 200/203, various Sonos (via Roon).