Hi Umberto,
Thanks for your reply. I will work through the links you sent me and see how I get on.
I didn't explain in the first message, all other things that require audio on my system work fine. GSX is the only silent product.
I am starting with downloading the latest Realtek drivers for the onboard sound and see where that takes me, but clearly something has been changed during one of the routine Windows updates.
Regards
Mervyn