SOLUTION FOUND. The problem was so simple I am embarrassed.
The tape-out connector on this new receiver is not working . I spent a lot of time trying researching the possible causes on the internet, money for special order cables, and new pre-amp. No solution.
Then I forgot the new technology and returned to basics-to solve a problem try the easy options first. I then removed all the expensive cables and pre-amp. I reconnected the original cables to another audio-out on the receiver and VIOLA! clear and audible sound from the computer speakers. I then tried the other audio-out connectors and they also worked.
What have I learnt? Too much information, at times can be useless. I would have first used the simple options If I had not read so much, on the inernet, about the need for special cables,pre-Amps and mixers, special sound cards and recording software,the difficulties of transfering LP's to CD's via a turntable, receiver and computer etc.
Next task-reducing the snaps, pops and crackles in the sound from the LP's. Simple solution to start-wash with small amount of mild dishwashing liquid. THEN use the sound suppressing technology.
I am now using the standard hardware and software that came with my computer. I may change the soundard just to get better Bass control and digital connectors.