@jens @sixohsix @mcc ok let's rephrase the question: "I have a set of packets that have time stamps. Half of them have a known interval, but have an arbitrary uncorrelated origin. The other half have an unknown interval, and an arbitrary uncorrelated origin. In both cases, the origin can randomly *change* while playing. How do I put all of these into one common reference frame?"
The answer of "ALSA uses one of your system's clocks internally!" does not answer this question.