Linn does not see Melco NAS

[simoncn]

I would not expect that a Denon HEOS speaker would cause this problem.

In a situation like this, I would suggest you create a minimal test network with just your router, the Melco and the Linn, preferably attached directly to the router with Ethernet cables. If you still see the problem, it is caused by the router. If you don't see the problem, add back other components one by one until the problem starts to occur. The last component that you added back should be the cause of the problem.