URGENT: No Sound in Reaper

I was working in Reaper with sound working fine (i was set to waveout at the time) and the sound just stopped coming out. The sound works fine on my laptop outside of Reaper. Everything is set normally, nothing is muted and all volume bars are playing etc. I downloaded ASIO4all and set my audio in Reaper to ASIO but still no change. I've attached some screenshots PLEASE help!

What OS? Did you do anything or did anything happen at the time the sound cut out?

Using VISTA nothing happened at all, just pressing space to stop and start while editing midi. Also just noticed, using ASIO4all, theres a red cross next to speaker, but all the suggestions it gives are done, and still no sound.

unchecked that setting and still nothing! wavetable is enabled

Ahh, so I un-tick the "allow applications" thing on my audio device but DISABLE Wavetable in Reaper? I've just done that but still nothing. I'll reboot and see if there's a difference.

That's done it, thankyou so much!!!

I just don't understand. I've tried everything that ive rwad in the forums and j still cant get sound. its not my audio interface because I can get other (trial) DAWs to work..