Ad-hoc connections broke with Mavricks and no longer works with SL Remote or QMix. I ran into this when troubleshooting another problem with SL Remote and QMix not connecting through a router. IPad and IPhone would see the StudioLive mixers but pressing Connect would not do anything. Anyone suffering this problem should look at disabling any firewall on the Mac. That resolved the connection problem for me. See the SL Remote Troubleshooting guide for additional information. There is a TCP-IP port that the McAfee firewall was blocking in my case.
I have same problem. Sometimes it works and sometimes it doesn't. Also not getting any pink noise when using Smaart to.EQ the room. If you are using 2x16.4.2 try disconnecting one of the boards.
Looks like the internal version number in UC 1.7 was not updated and appears as 1.6.5451, so this is very misleading. Also the SMAART features seem to not be working if you have two StudioLive 16.4.2's linked together. Unlink the Firewire cable and UC 1.7 new SMAART will work. Something I hope they can fix in UC v1.7.5.