Anyone had experience changing from AT&T T1 to T1oIP using RAD IPMux-24

[Astro2P25]

I am having difficulty getting Tenrs channel banks to pass audio and E&M over the DSM II cards. This is a single site off the Microwave that is connected to the simulcast system.
Works fine on the AT&T T1 (when its actually up) It seems AT&T knows that T1 is a dying transport and puts no priority on getting it fixed when it goes down. Also its a lightning magnet for the site.
Here is what is we are dealing with.
Motorola smartnet Astro / Analog hybird using Tensr channel banks with SRU cards for the DCB link and the V.24 (astro) links
DSM II cards for the analog links. (can't find any info on the these DSM II cards from Zhone if I remember correctly they were made specifically for Motorola simulcast)
I can get the T1 to link up on the IPmux24 via the local cable company's fiber "point to point" IP network.
After several alterations to the clocking source on both sides I was able to get it to link error free for over 48 hours. Feeling pretty good, I decided to bring the site onto the link but unfortunately the Analog transmissions were not passing audio and I was not able to key the stations via the SDA simulcast distribution amplifier to check simulcast distortion.
I have a feeling that my clocking scenario is still a problem however I tried every possible scenario.
My question is, how does the AT&T TI pass clock timing differently than the RAD IPMux?
Is it possible I will need the RAD T1oIP converter the has an external clock source port so I can inject the 1PPS signal?
Any input would be appricated

Tony

[train_radio_guy]

Although I've been out of the 2-way Radio Industry for a few years, I've worked in the Telecom Industry for nearly 23-years. When it comes to timing on T1/DS1 or HiCap Circuits, the timing in the Central Office is derived from a centralized BITS Clock. Typically, they use a GPS Timing Source as the primary source, with a secondary source coming from a larger office upstream (i.e. Tandem). Although the transport equipment, which carries the T1 Circuits is typically timed off the BITS Clock, the T1's themselves are usually loop-timed from the originating source. In your case, AT&T being the local Telecom, would most-likely provide timing.

Years ago, many of the wireless carriers opted to have a local GPS Timing Source, and discontinued relying upon the T1 for source timing. If you're attempting to migrate to a different carrier, for a VoIP Solution, I would be asking very pointed questions like are they providing QoS (Quality of Service) for your voice packets, through their entire network. In addition, do those VoIP packets traverse other networks, while en-route to their final destination? In terms of synchronization, if the VoIP packets are not arriving when expected, I would anticipate drop-outs or no audio path at all. QoS has to be end-to-end - it's only as good as the weakest link.

In the T1 world, we would be looking at timing slips on the T1. In the VoIP world, this becomes a slightly different 'animal'.