Double Ringing effect
Occasionally an outgoing call produces a double ringing effect. It will sound like the ring is pulsating or overlapped with another background ring. This is an SS7 issue. We send out the equivalent of an Invite, the other side responds back with 'yes, found it, ringing it'. Then it comes back with an in-band calling-progress. So we end up sending you two 18x returns, one for each of the PSTN side indications.
We can adjust your current media profile in our switch to eliminate the extra 18x signals.
If you have this double ringing effect please contact support by email at firstname.lastname@example.org or by phone at 8669284465 options 1-3-1.