AVR routs monomixed parts of DD2.0 content from TV apps to center even when not upmixing?

[XaVierDK]

The setup:
AVR: NAD T758 v3
TV: LG C3 OLED

After a longer period of running 2.1 and 4.1 for several reasons, I finally had the chance to reintroduce a center channel speaker to our system.

Set up things as usual, ensuring no upmixing was selected as default and so on.
Watching 5.1 content from the TV's built-in apps are played back perfectly with no issues. However, all 2.0 tracks from the TV when outputting bitstream result in any monomixed parts being muted, but only above the crossover point.

If I turn on Dolby Surround, the missing audio is output correctly through the center channel.
Stereo tracks from streaming on the receiver are fine, as are 2.0 PCM.
I have reset the HDMI ARC handshake and reset the TV.
Do you guys have any suggestions or possible causes? My next moves are a reset of the AVR and a new HDMI cable.

This TV and receiver have previously worked with a 5.1.4 setup with no issues pertaining to stereo playback.


Thanks in advance

 

[TLS Guy]

The setup:
AVR: NAD T758 v3
TV: LG C3 OLED

After a longer period of running 2.1 and 4.1 for several reasons, I finally had the chance to reintroduce a center channel speaker to our system.

Set up things as usual, ensuring no upmixing was selected as default and so on.
Watching 5.1 content from the TV's built-in apps are played back perfectly with no issues. However, all 2.0 tracks from the TV when outputting bitstream result in any monomixed parts being muted, but only above the crossover point.

If I turn on Dolby Surround, the missing audio is output correctly through the center channel.
Stereo tracks from streaming on the receiver are fine, as are 2.0 PCM.
I have reset the HDMI ARC handshake and reset the TV.
Do you guys have any suggestions or possible causes? My next moves are a reset of the AVR and a new HDMI cable.

This TV and receiver have previously worked with a 5.1.4 setup with no issues pertaining to stereo playback.


Thanks in advance

I think you have had no replies, as we also need to know your exact settings. Your question can not be answered as you posed it. That receiver is quite old and not well thought of. One strange thing I did find in the manual, is that if you select stereo, the default is Dolby surround, which is nuts. So if you select stereo, you then have to select none. If you don't you will get Dolby surround and therefor get output from the center channel.

After looking into it, I am certain this is not a device I would want to own.