Unable to get an IP address through my switch

I have an S40 as server powered by an S60 and a DEQX Pre Mate Plus as player. Streaming is fine when connected straight from a port on my TP Link VR 1600v modem router.

I also have a TP Link unmanaged 5 port switch fed from the modem router and when I try to stream by connecting the S40 to the switch I am never able to obtain a 192 type IP address.

It’s not critical as I can always stream direct from the modem it’s just that it would be neater cable wise if I could use the switch.

All the ports on the switch are fine my iMac and TV etc all work from it. I have tried all the usual fixes different cables, power cycles, address reservation in the modem. Does anyone know of a setting in the modem that may fix this.

Thanks