Bursts are eight times longer than expected

[vtmmm]

It seems that each burst has ~26.7 ms of data (which is expected since that matches the AIS timeslot duration), and then ~187 ms of a constant carrier. The entire thing lasts about 213 ms, or 8 times longer than intended.

I don't believe the incoming PDU has a ton of trailing 0s or anything, so I'm not sure why this is.

A single message burst open with Inpspectrum showing 26.7 ms of data followed by a constant carrier:

To generate this file, I'm using ais-simulator.grc but I've replaced the Omso sink with a File Sink, then generating one message from the ais-simulator web interface.