Question RX-V581 Program help - Stereo sources and surround

[StoufferTheCat]

Sorry - probably poor subject title. Let me explain the situation.

I have a Yamaha RX-V581. Input 1 is a SkyHD box, Input 2 is a PS4.
The "Program" set on the Receiver is "Straight". So I was watching, for example, Game of Thrones and I'm getting 5.1 output. The front display indicates all 5 speakers are being used, I'm getting the full surround.
Some programs on Sky are giving me a stereo output, and when this happens I'm only getting sound through front speakers. The display on the front of the Yamaha indicates the surround speakers are not being used, and if I check the "input" it confirms 2.0.

I am 99% sure that up until 5 days ago when I unplugged everything for a front room refit, even if the source was 2.0, I was getting audio output through all 5 speakers.
What I'm not 100% sure is which "Program" I was using.

So, when I'm playing a Blu-Ray on the PS4 or watching something on Netflix etc that outputs in 5.1 I obviously want the Receiver to do all of the decoding.
However if I'm outputting something just in stereo, an example last night I switched to Sky Atlantic where there was an episode of The Sopranos on, I want the receiver to effectively switch to a "virtual surround" and give me output from all 5 speakers.

Which settings do I need to enable on the Receiver for this to happen?

Thanks.

 

[dante01]

If the receiver is set to STRAIGHT then you'd only get audio via the speakers the incoming format has associated channels present for. You'd only get audio via the front left and right speakers in STRAIGHT mode if the incoming audio was only 2 channel stereo in nature. You'd need to use one of the upmixing modes associated with SURROUND DECODE modes if wanting all your speakers to be urilised if dealing with sources only encoded with 2 channel audio.

When watching content that only has stereo audio and if wanting to create pseudo multichannel 5.1 surround then do not use the STRAIGHT mode and use one of the SURROUND DECODER options available to you. Repeatedly press the SUR DECODE button on the remote to cycle through and engage these modes. Either Dolby Surround or Neural:X will probably be the most appropriate options to use.