Ah yeah, 4K and HDR would be a problem.
And looking at the specs, your receiver doesn't support high-res audio formats on the HDMI-in ports for some reason.
So yeah, I'd suggest getting a better receiver soon, because PS4 direct to the TV will give you 4K and HDR, but you miss out on 5.1/7.1 LPCM, DTS-HD, etc.
PS4 to TV can only do 2.0 LPCM, or lossy 5.1
But I have my receiver connected via the HDMI-OUT (ARC) on the receiver, to the HDMI 2 (ARC) on the OLED.
I was checking this guide and it says in this section:
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"Essentially how we're going to get HDR visuals on your TV screen and still keep your surround sound intact is by separating the visual and audio streams. We'll achieve this by connecting your PS4/PS4 Pro directly to your TV and then connecting your AV unit to your TV, via an ARC-HDMI port.
ARC stands for ‘Audio Return Channel' and does pretty much what it says on the tin, as it splits the audio stream from the visual stream and sends only the audio from the device (in this case the PS4/PS4 Pro) to your AV unit. The upshot of this is that only the audio ends up going through the AV unit and not the visuals, since the latter will be going through your lovely HDR-compliant TV instead.
The majority of AV receivers manufactured over the last three to four years typically include a HDMI-ARC connection, and when it comes to hooking it all up, you want to make sure that you're using HDMI 2.0a cables too, simply because any earlier standard cable will not carry the HDR signal.
Once your cabling is all in order, you then want to enable HDMI-CEC in both your TV and your AV receiver as this will allow your AV unit to stream audio from your TV, without taking the video stream along for the ride too. Naturally, implementation of HDMI-CEC will vary between the various brands of TVs and AV units so give your user manuals a flick through so you know how to access it.
After you've paired your AV unit to your TV in HDMI-CEC mode, you then want to set your AV unit to receive from ‘TV' (rather than BD, DVD or whatever other preset you have). Once you've done all of this, turn on your PS4/PS4 Pro and you should now have all that 4K HDR goodness going through your nice expensive TV without any degradation, while your surround sound audio is pumped through your surround sound speaker setup." (
http://www.psu.com/feature/31139/ps4-hdr-update-how-to-fix-ps4-pro-surround-sound)
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I followed this guide but I don't know what your expertise have to say about this. Thank you for answering my questions.
Oh and my receiver has support for DTS-HD and True Dolby HD, don't know if that is relevant.