Loss of ring back tones when calling a TWC/Spectrum phone
Posting for my brother/SIL, who have a TWC/Spectrum phone.
Strange problem - For the last month or so, some callers to their phone do not get ring back tones after dialing. (Ring back tones - what the caller hears to indicate the remote phone is ringing.) Causing some callers to hang up because they think they got a bad line. Others, including Spectrum tech, do hear the ring back, Their phone (destination phone) DOES ring, even if the caller does not hear the ring back.
If the caller is calling from an AT&T or T-mobile cell phone, then they do hear the ring back. If the caller is calling from a Verizon or Sprint phone, then there is no ring back, just what sounds like a dead line. It occured to me that AT&T and T-mobile are GSM phones, and Verizon and Sprint are CDMA phones.
Is there perhaps some difference between the way a GSM and CDMA phone connect that could be causing this issue? Or any other ideas?