sound from HDMI for an GTX260 Nvidia card with 2 heads

On this PC, with this video card, I cant produce any sound to the monitors.
I connected 2 HDTV on this cad, and video is ok, but no sound.
But the nvidia driver shows the 2 sound destinations (tv)
When you open up playback properties, the only one I can use is speakers, there is no tv showing for playback.

So why is this, is it the nvidia card?

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Reading about this, it can pass audio using the spdif plug on the board into that video card. so wired up a cable and tested it but still no sound over HDMI.
I also do have the HDMI +4 dvi adapter going to the TV.

I tried setting spdif sound as default and the windows screen shows the bar moving up and down, but no sound to the telly.over HDMI

Anyone have a clue? No desire to buy a new video card, the old one works on video and ought to work on sound.

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It may be I have to use a sound bar and use either spdif out on the motherboard, or use the 3.5mm audio jack.
I am not even sure buying a new video card will work. I am opening a new chrome window, dragging it to the TV on the right, then playing an Amazon Prime video, All I see is the picture when sound set to spdiff, sound set to speakers, sound plays through my PC speakers.
The spdiff bar is moving so it has a signal. dont even know if what i am doing is possible, sometimes PC component makers do weird things with wires, ports and hardware, and stuff does not work like you thought it should.

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OK, I SOLVED this puzzle. Both my wire plugs were reversed on MB and on video card.
I discovered that using my ohmmeter on the video card, the ground pin will read only a few ohms.
The MB manual showed I had the plug flipped, ground and 5v power. What fooled me was my cable that came with video card, they had black as spdiff and white as ground.. go figure, so I made black ground and white spdiff, which makes more sense. And I looked at a generic spdif 3 wire plug, not specific to this board.

I set sound output to spdif, and interestingly, I hear sound out of speaker and spdif at same time./.