Does the Olympus AS-2400 support two-channel playback?

Yes, sort of but mostly NO.

I know this is a very confusing answer but it’s a confusing problem.  The software will playback audio files recorded on devices that record in stereo, like the Olympus DS-71 but only if they are using a standard microphone.

If you plug in a microphones with two-channels (Olympus ME-30), the AS-2400 will only playback the audio recorded on the left channel.  The AS-2400 (DSS Player Standard) does not allow you to separate the channels for playback.

If you need a software solution that fully supports two-channel recording and playback with the ability to separate right and left channels, you will need the Olympus AS-5000 Transcription Kit (DSS Player Pro Release 5.0.12).

Verification Source: In-house testing