I am new to this community and need some help if possible.

I have a Bravia XR 65A9k TV and Sonos Arc and 2 x Era 300 for dolby atmos connected via eArc.

When looking at the Sonos app to establish the sound track for movies I am playing either via my Panasonic 4k player or streaming via Netflix or Prime, if the films have Dolby Atmos I get that sound track displayed in the Sonos App and also pressing the 'Audio' button on the TV remote displays TrueHD Atmos. However when I play films from my NAS connected via Ethernet LAN using VLC app installed on the TV, which supports Dolby Atmos, all I see is Dolby Digital Plus 2.0. The films have both TrueHD Atmos and DD5.1 sound tracks available. If I switch to the DD5.1 sound track, that is then displayed in my Sonos App.

If I use the default media player on the TV it only supports DD5.1 sound tracks and there is no sound if selecting TrueHD

I have spoked to Sonos support who have run diagnostics and assure me that the Sonos speakers are fine to receive TrueHD Atmos.

They believe the problem is between VLC and the TV but given I can play Atmos via other apps such as Netflix and Prime streaming services there should not be any difference streaming via VLC/NAS all of which go through the tv.

I have passthrough set and audio output to dolby audio.

Finding it very frustrating that I cannot play films stored on my NAS with TrueHD Atmos and hoping someone may be able to offer advice?

Many thanks