No devices available on Spotify Connect. Was OK. Now they've disappeared.

[NigSums]

I use Spotify connect on a Macbook Pro connected via wi-fi to BT Broadband Hub and then by LAN cable to Marantz CR611 Amp/Music Streaming device. This has worked fine for a few days, but now there are no devices showing so Spotify only works on the laptop. Have tried rebooting the router, the Mac, the Marantz several times. Have checked all software is up to date. Have made sure all devices are on the same network. I have Spotify Premium and cannot use it. Very frustrating. Any ideas? 

[sharkbait10]

Hi, do you have different ssids and passwords for the two networks (the one from your device to the hub and the one from the hub to the router)?