Here's an intersting one that seems to have no results on google or in debug info:

I have an SPA-2102 (firmware 5.2.10) that returns 486/Busy Here when a call comes in to the active line.

"call waiting" is turned on, so it should be beeping in instead...

I got these logs off the SPA but it doesn't seem very helpful: (and there should be more, I think)

==> /var/log/syslog <==
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il [0]<<$FreeSWITCH: 5060(1148)
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il [0]<<$FreeSWITCH: 5060(1148)
Jan  7 14:38:14 INVITE sip: 1632@$CLIENT_IP:5060 SIP/2.0#012
Jan  7 14:38:14 INVITE sip: 1632@$CLIENT_IP:5060 SIP/2.0#012
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il [0]->$FreeSWITCH: 5060(312)
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il [0]->$FreeSWITCH: 5060(312)
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il SIP/2.0 100 Trying
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il #012
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il #012
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il [0]->$FreeSWITCH: 5060(338)
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il [0]->$FreeSWITCH: 5060(338)
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il SIP/2.0 486 Busy Here
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il #012
Jan  7 14:38:14 $CLIENT_IP.smc.012.net.il #012
Jan  7 14:38:15 $CLIENT_IP.smc.012.net.il [0]<<$FreeSWITCH: 5060(334)
Jan  7 14:38:15 $CLIENT_IP.smc.012.net.il [0]<<$FreeSWITCH: 5060(334)
Jan  7 14:38:15 ACK sip: 1632@$CLIENT_IP:5060 SIP/2.0#012
Jan  7 14:38:15 ACK sip: 1632@$CLIENT_IP:5060 SIP/2.0#012


I saw one suggestion to do a factory reset that fixed the problem, but that's a bit troublesome at the moment since the client can't load provisioning files (dumb network.)

-Avi Marcus