Visualization differences between soundcards

Hello!
I’ve just catch a very strange behaviour of kodi (16.1).

The visualization Waveform does not show the same if I use two different soundcards… (it is in fact the same problem with all vizualisation addons…).

With my edirol UA-20, the waveforms are just what they need to be, with my C-Media card, the waveforms are strange and glitchy.

With a little Addon, I’ve successed to read the pAudioData from the AudioData functions…
and they are different if I changed the soundcard!

Do you have some similar problem?
Could it be link to stereo or 7.1 soundcards difference?

I hope you can help me!

amand.