I'm running two R800s with a Tascam DR40 to capture external audio. I'm syncing all three feeds into Final Cut. The two pieces of footage sync up perfectly fine, however the DR40 audio loses sync by the 2 min mark. Typically, I'd see this with a sample rate issue (44.1 vs 48) but I can't find anywhere that shows what the R800 is recording audio at.
Camera footage is recorded at 1080P / 60P / 35 Mbps
Audio is a 192k bitrate MP3 file recorded at 48kHz.