Listening to music on my PR1.3 N9 I suddenly realized the music was in mono. The same FLAC played in stereo just fine on the desktop. And other FLACs, from the same musician on the same album even, were in stereo on the N9 as well.

Back at home I noticed the FLACs playing in mono are bit 24 bit per sample, while the others are 16 bit. I'm not sure whether it is downmixed to mono, or that only one channel is used, although I guess it's downmixed.

Being FLAC, I of course could downsample the affected tracks to 16 bps without losing quality on the N9, but I'd rather just have it work as intended.

• Why are 24 bps FLACs played mono? Bug in gstreamer? PulseAudio or PulseAudio configuration?
• How to fix it?

share your media file first

How come some are 16 and some are 24 bit, probably something fuxored while encoding?

I'd guess the N9 can handle only 8 bit per channel, though it's not mentioned in the specs.
24 bit means 50% more data, so probably the 2nd channel gets skipped.
Also, it's very unlikely that you can make out any difference at all, so I'd simply say always use 16 bit (like CDs). On the desktop too, if you can live with that quality.

With vinyl rips the difference is audible between 16bit and 24bit on some albums. E.g. the bass is richer. But N900 doesnt support 24 bit ogg, so I always dither for N900

Sample. 10 seconds only, as per Fair Use.

Yeah yeah I know I can't hear the difference between lossless and a well-encoded 128kbit opus/vorbis/mp3/aac/whatever lossy flavor of the day. But when I pay for music I want at least CD-quality, to be able to convert to said lossy flavor of the day - if could be bothered to convert at all, which I can't, with 64GB storage.

But all that is not the point. The N9 is very capable of playing 16 bit per sample stereo audio. These 24 bps tracks shouldn't be a problem: strip away the 8 LSB, and it's good enough. And indeed the N9 is capable of playing these files, but only mono. This isn't a hardware limitation, this is a bug. The question is: what is bugging, and can it be fixed.

No no, I mean 16 bit FLAC... just like CD's! You won't gain anything from encoding them to 24 bit.

Edit: true!

The FLACs are originally 24bps, as downloaded from bandcamp. I didn't transcode them. I might be stupid, but not that stupid.

And the N9 is 16 bit per sample per channel, like CD. (these flacs are 24 bit per sample per channel...) Why do you think it's only 8 bit or even 12 bit?... 8bps would introduce a very audible hiss.

Well... it's a bug alright, but not in gstreamer:

and the clip is played back flawlessly, in stereo. It's just the default music player which b0rks here. Guess I'll be looking at those alternative players pretty soon . Leaves me wondering how the default player manages to mess this up. Does it use gstreamer as well?