I have the following topology
ext 200-->CME-A--WAN---CME-B---> ext 300
on CME A i have a VoIP DP to CME-B and vice versa. On CME-A I also have a POTS DP with the same pattern to CME-B what with higher preference for failed calls over IP.
What is happening is if i place the first call from ext 2xx to 3xx it goes over IP. If I hang up and dial the same number it routes over PSTN, and the next time I try it goes over IP....
If I take out the backup route over PSTN, I get a sucessfull call over IP, and the next call fails, and succeed again on the next call.....
What is going on?
running CME 4.2