Ruckus AP - faulty?

[smurfomatic]

One of our Ruckus 7372 APs is causing clients to disconnect, not giving them any network connection etc. Typically this is one that's in a building on its own, so no other APs nearby to connect to.

 

See screenshot of the Zone Director status page - the log part also reports a lot of "fails to join WLAN" errors. The PHY errors count seems high to me, considering there's only two clients and I restarted it about 90 minutes ago (PHY errors on g/n has gone up to 932 while typing this post). Another AP with 8 clients on it at the moment (someone hasn't switched off the bank of iPads!) has less than 300 and that AP has been on for 48 days having passed over 40GB of traffic in and out.

 

Is this a fault with the AP itself, or is it more likely to be an issue with the cabling between it and the rest of the network?