Does a key appear to go down on your virtual keyboard on screen when you use the mouse, even though there's no sound?
I'm writing the following assuming you're using the CS80V in standalone mode:
If it does, you need to check the sound is going to your soundcard. Click on the section marked `out' on the top right hand side of the CS80V window next to the percentage display. If your soundcard appears on the dropdown menu, click to select it. If it doesn't, click the CS80V's `file' menu and select `preferences.' See if you can find your soundcard on the board that appears when you do that.
If that doesn't help, post again saying what happened.
Do you have anything else connected to your PC that is getting sound from your soundcard? Can you play Windows Media Player or anything like that?
You can use the CS80V under a sequencer program and program the notes that way. I'm not an expert on seqencers, but someone else here, or Arturia tech support should be able to advise.
The advice I'd always give to anyone buying an Arturia softsynth is to have a good processor and soundcard. The Arturia synths tend to drive the processor hard. Regarding soundcards, I have an RME Hammerfall 9632, which works very well. There may be more recent cards with better specs, though, as I've been using it with my Arturia synths for about three years now. The RME has a MIDI socket so you can control the softsynths from a MIDI keyboard. Most soundcards should be the same in that respect. I'd definitely recommend that unless you use a sequencer. You won't get the full value from the CS80V if your only option is the mouse - though you will get some good sounds anyway.