I have two spa2102's connected to the fxo ports of a digium aa50 pbx. This configuration is used for an office with 18 extensions. I have a similar setup in my own office with a trixbox server, digium fxo card and 12 extensions. All phones are grandstream bt200.
In both cases I have completely disabled call waiting at the phone, on the pbx and in the 2102 yet I still get random call waiting tones. Sometimes they happen when there is an incoming call on the same 2102, sometimes when there is an incoming call on the other. Sometimes the tone happens when only 1 line is in use and no incoming call. I am unable to reproduce these tones on demand. Does anyone have any insight into solving this issue? I have been in contact with the manufacturers of the phones, the pbx and linksys but have received no answer yet.