Judicat0r: That is weird, I'm thinking at some kind of driver issue/setting.
Maybe the driver is not properly seeing your monitor as a audio-capable device, If you want to continue to troubleshoot this, you can try to hook up a TV to your HDMI or DP, that way your driver should see an audio capable device connected to one of its ports and you should ear sound.
Zimerius: Well, for now it is oke the way it is presented. Tomorrow the show continues if the optical cable arrives.....
thanks for the input so far, when searching around on the internet i did come across some manuals written by people who also use the gpu port to power speakers, didn't have the time to read through but if i do and there is some change i'll be sure to write a report ;-)
Let me give you some advice:
Don't use an optical cable. The S/PDIF standard which defines these cables stretches back to the time when CDs where new. And that's what they were designed for. To transfer CD music (44100 Hz, 16 Bit, 2 channels) from the CD player to the receiver. They are not capable of transporting modern requirements (my receiver supports up to 192000 Hz, 24 Bit, 8 channels).
So unless you only have a stereo setup and don't care about higher sample rates you don't want that. If you own a 5.1 setup and want to listen to high definition content (e.g. Bluray movies with DTS HD MASTER AUDIO) you want to go the HDMI route.
For troubleshooting try the following:
*) Make sure you have the latest version of Windows. I remember hearing there was a bug in some versions of Windows 10 that interfered with audio over Displayport/HDMI.
*) Check the cable. Sadly not all cables have the same bandwidth. The bandwidth depends on the HDMI/Displayport standard version the cables were produced for and some standard versions even allow for different cable bandwidths. Not every cable has enough bandwidth for high resolutions + audio. You need to make sure you are using a cable that has enough bandwidth to support your resolution of choice with audio. And of course that the HDMI/Displayport version your GPU and your monitor use is capable of using it as well.
*) According to your pictures the NVidia driver sees your equipment as audio capable. That is a good sign but is that device set as default sound output device in the Windows Sound Settings? That's something you really need to check. Especially if you have more than one audio output device (which most people do since most motherboards come with an audio chipset). Windows 10 just loves to change the default device for no reason at all. The only way I have found to prevent that is to disable all devices I do not regularly use.
*) Actually try a HDMI cable. I've had a look at the pictures you posted. Sound3 shows that you have connected your equipment to a Displayport connector. If everything works as it should it should not make a difference but I have already heard reports of audio trouble with Displayport on a system with no trouble using HDMI.
I've been using the NVidia audio driver connected to a 5.1 setup for many years now and I am very happy with it. I hope you get your setup running as well.