[MisterBee]

Thanks for your suggested action. First I can confirm the the Audio leads are on the I/O plate. I download the VIA 4 in 1 Drivers from the ECS website. I then unzipped them and installed. I chose to install the 3 items that were identified on the screen. Installation seemed to run normally but on completion I was informed that no drivers had been installed. However a restart was directed so I did that and then installed the audio drives downloaded earlier. Regrettably after a further restart the machine was in the same condition as before. Just to make sure I had not made a mistake I repeated the exercise but with the same result.
As you imply that the problem lies with the drivers for the onboard chips I have dabbled with the CD that was supplied with the board but there are a large number, six I think sound drivers and having had three crashes I am now nervous about trying these at random.
If you more suggestions I would like to solve the problem but my patience is wearing thin so guess yours must be too. I saw one solution suggested is to buy a soundcard but would this work I wonder?
I have to have a break for a few days, going away not having a breakdown, so will come back with renewed enthusiasm and perhaps find some more sensible ideas to try.
Once again many thanks for your time and effort. Very much appreciated.