[Top Jimmy]

Darryl makes a point, but I would say that you haven't provided enough info to determine anything concretely. If the timing drifts immediately, then it is what Darryl said. If the timing drift isn't noticeable until a couple minutes down the timeline, then I would say that the problem is clock drift between two unsynced digital clocks.

In other words, if you record independently on two different AD converters, you can't expect them to be in sync. The way to solve this issue would be to record in time in Audacity with a source timing track from the Pro Tools session. Whether it be a click or a rough mix doesn't matter.