Originally Posted by DSperber
Let's clarify here...
(1) You have fed HDMI audio+video output from two different PC's into the HDMI input of the 103? That's the basic experiment?
What is the actual content you're playing on the PC which is then feeding the 103? Is it some video clip, or standard HDTV recording (with DD5.1 audio) from a TV tuner card, or DVD/BluRay movie played on the internal CD/DVD/BD drive of the PC through some commercial software? If HDTV or video file, how were the files produced... specifically what was the recording/encoding method, and what type of audio is inside of it?
(2) Sending digital audio out via HDMI/DP connector from a PC requires that you set things up properly in the audio output, using Playback Devices (from right-click on speaker icon in the System Tray). When you select the HDMI output as the default in Playback Devices what do you have set in Playback Devices -> Configure, and what do you have set in Playback Devices -> Properties -> Supported formats?
Do you have multi-channel checked wherever possible (for both speaker configuration as well as multi-channel source formats)? The PC is not down-converting multi-channel source to stereo output, is it?
(3) And you say you've also tried to feed the HDMI output of a separate second external BluRay player (as the third test source!) to the HDMI input of the 103? Why would you do that?
I'm actually quite surprised this would work at all, but for sure you should simply be playing BluRay discs on the 103 itself, natively... not feeding the 103 HDMI output from some external BluRay player as external HDMI source input. Why would another BluRay player be your source device, and not the BluRay mechanism of the 103 itself?
(4) Can you provide details of the cabling setup on the PC's, and then the output of the 103? Cabling "schematic" from the PC to the 103 and then out of the 103.
Where does the video output from the 103 go? Directly to an HDTV, or to an AVR and then on to an HDTV? The PC digital HDMI/DP output of the PC is providing both digital audio and digital video, and I'm curious how the digital video is getting from PC to the HDTV.
(5) What digital connector is on the PC? For example, is it full-size HDMI output from the PC's discrete video card, or is it an HDMI output from onboard connector of the motherboard? Or is it micro-HDMI, or DisplayPort, or miniDP, or exactly what type of connector at the PC end?
And then are you using an adapter (PC connector to full-size HDMI female) for the PC connection plus a separate full-size male-to-male HDMI cable (going from the HDMI female end of the adapter to full-size HDMI at the end feeding the 103)? Or are you using a straight-through cable with the appropriate correct connector at the PC side and going to full-size HDMI at the 103 end?
I'm just very suspicious that the "noise" you are hearing out of your 103 DAC -> analog sound system, which starts off as digital audio in the PC, may be originating with the PC setup or digital audio/video content files you're playing.
I mention this because I myself use digital audio from my Lenovo W530 laptop (with nVidia K1000M graphics) via miniDP->HDMI to both my Panny 65VT50 HDMI input directly, as well as to my 103 front external HDMI input (which then feeds my Yamaha AVR for multi-channel sound and delivering video to my Panny), again without an audio or video issue.
I've played both HDTV recordings (copy-freely WTV files from Windows Media Center and TV tuner cards) as well as streaming media (e.g. Netflix, Amazon Prime, HBO Go, Showtime Anytime) that includes high-quality 1080p video and multi-channel audio, again with no observable audio issues or underlying "noise". And I'm very very particular.
1. I just played 2 channel music. Flac files in foobar, but the problem was the same for other media types.
2. Everything was set up correctly.
3. This was just for troubleshooting. To try another different source. It's just an HDMI bitstream so the 103 doesn't care what source you connect as long as they both support the same format.
4. Both audio and video from PC to OPPO via HDMI. From oppo to poweramps using analog RCA and to projector using HDMI.
5. Full size/standard HDMI.
I've just before i read your comment found out what the problem was. The auto mute feature is implemented differently for the different sources.
When you play CD, bluray or network stream the auto mute triggers as soon as the playback stops. This prevents the noise floor from being audible when no sound is playing.
When you are using HDMI in on the other hand the Oppo doesn't know when the playback stops and starts. It's just receives a stream.
That's why there was an audible noise floor when I was using HDMI, but not when I played CD or streamed over the network. The SNR was the same for all inputs, but the auto mute works differently which hides the noise for all inputs except HDMI.
I hope this can help some one else because it took a while with different measurement and listening test before I figured it out.
But I'm still a bit disappointed that the SNR isn't better on the 103. I guess I have to look for a 105