Normally Voukoder Pro picks the audio layout that gets exported from Premiere / Media Encoder. I will investigate this.
What error did you get? Did you check the Voukoder Pro log file?
I didn't think of copying it at the time. I also noticed that I wasn't running the latest version after I posted this. I updated and I ran a couple of tests with a random 5.1 AC3 MKV sample:
1. Exported as MONO. Output: a 1.0 track.
2. Exported as STEREO. Output: a 2.0 track.
2. Exported as 5.1 SURROUND. Output: ERROR.
Error compiling movie.
Export Error
Exporter returned bad result.
Writing with exporter: Voukoder Pro
Writing to file: I:\test_1.mkv
Around timecode: 00:00:00:00
Component: Voukoder Pro of type Exporter
Selector: 9
Error code: -2147287026
The VoukoderPro log doesn't show any new entries since the last successful encode.
I kept the Voukoder settings the same for all tests: eac3, 320kbps. When the error occured, I tried a few things with no success:
• raising the bitrate to 640kbps (in case 320 was too low for 6 channels)
• changing the audio channel layout from 5.1 to 6 mono clips in the editor, just in case, and exporting again.
• switching the export codec to AC3.
• exporting through Premiere instead of Media Encoder.
• loading a 7.1 test video (another MKV, TrueHD) and tried exporting that one at 5.1.
Same error with all. I realize it's too obvious an issue for no one else to notice it and it's probably something peculiar on my end, but I don't know what can possibly be causing it. It's a clean, up-to-date Premiere/Media Encoder installation. I have Influx (an importer/decoder plugin, https://aescripts.com/influx/) installed which could be the thing that throws Voukoder off, but I configured it to only override not natively supported codecs so AC3 should still be decoded by Premiere. Weird.
Oh, and a related question, if you can't set it up directly in Voukoder and there's only these three settings (mono, stereo, 5.1) that are available, how would you export something like a 7.1 file with a format that supports it?
Just a small update, since I was looking for a workaround to export 5.1 in the meantime:
I tried exporting in regular Voukoder (something that's worked perfectly before, on a 2024 version of Premiere) and got the same error. I'm on Premiere 25.2.0 right now. Just to make sure it wasn't related to the Influx plugin or the MKV format (Adobe mentioned working on it in the changelog), I imported a plain WAV audio file and tried exporting it in 5.1. Regular Premiere export options (MPEG4, FLAC, Waveform Audio) exported without issues. Voukoder gave the same error.
If nobody can't reproduce, can it be related to corrupted preference or something? I tried deleting preferences.json but nothing happened. Anything else I could try?