Playback distorted


as a total ardour-noob I am just trying to check if my setup is ok and I am already failing with the most basic task imaginable: Importing a wav-file and playing it back.

I am on Debian testing with ardour 8.1.0 and for the sake of this exercise I have shutdown pipewire and use ardour with alsa.

So I create a new session and import a wav-file which shows up as a new track, waveforms are displayed, everything looks fine, but when I now try to play it back I get extremely distorted sound (it is recognizable though) and the speed of the playback also is too slow…

Could someone please enlighten me what may be going wrong here?

Is the session sample rate the same as the wav file sample rate?

Yes the rates are the same, but I have found that the problem seems to be caused by the soundcard.

When I use the integrated sound card of my mainboard or an usb-soundcard everything works fine, but when I use the hdmi-output of my nvidia card I get this problem…

It is quite likely that the HDMI output only supports 48k even if it seems to report working at other sample rates.


Also try to raise the Jack buffer size by an order of magnitude (which is the solution for my KDE Slimbook, with Ryzen/AMD graphics rather than nvidia).
To begin with, aim for a delay of at least 100ms, and then try raising or lowering it, until “it works”…

I have made some further experiments and it seems to depend on the configured buffer-size for the nvidia-card.

eg if I choose 1024 samples I get this distortions, if I choose 4048 samples everything works fine.

Can someone explain what exactly is going on here?

HDMI requires a min. buffesize of 4096 samples/cycle (and 48kHz sample-rate).

See also

PS. HDMI not really suitable for pro-audio, it is intended for consumers.