Avant 55 Dolby from laptop

Hello all

In preparation for the F1 first race today i connected my laptop to the TV.

I noticed I have PCM2.0 via HDMI from the laptop

This I changed via the control panel sound settings and all speakers play the test sound (windows 10) so the Chanel coding is working.

For some reason when i play anything at all the center speaker is silent until i set HDMI back to stereo.

Any idea’s?

Cheers

Sean