[Nouveau] libva problem?

[James]

I am playing videos from my lubuntu computer to my tv through the hdmi
interface on my video card.
It mostly works.
Some sound doesn't and I think it is related to the audio code.
A52 Audio (aka AC3) (a52) works.
It seems MPEG AAC Audio (mp4a) doesn't work.
I checked a video that used to work and it doesn't work now.
It has the mp4a codec also.

The one that used to work shows this in Tools/Messages:
vdpau_avcodec error: decoder profile not supported: 7

The new one that doesn't work shows this in Tools/Messages:
vdpau_avcodec error: decoder profile not supported: 8

I think it might be related to the noveau video driver:
$ vainfo
libva info: VA-API version 0.40.0
libva info: va_getDriverName() returns 0
libva info: Trying to open
/usr/lib/x86_64-linux-gnu/dri/nouveau_drv_video.so
libva info: va_openDriver() returns -1
vaInitialize failed with error code -1 (unknown libva error),exit