I just bought an AS5300 to play with a few months ago to see if I could get 56k modem connections to work over VOIP. SIP channels -> voice card -> out a T1 (ne

I just bought an AS5300 to play with a few months ago to see if I could get 56k modem connections to work over VOIP. SIP channels -> voice card -> out a T1 (network) -> in another T1 (CPE) -> to DSP modem. (Or dialout, DSP modem -> out a T1 (CPE) -> in a T1 (network) -> voice card -> SIP. It just -doesn't quite- work. I can get 14400 no problem, but V.90 doesn't seem to entrain. Still troubleshooting (could be undesirable jitter buffer settings on my ISP side). I just barely missed end-of-sales of ISDN BRI in my area which could have been useful for get to the PSTN at high quality.