Pioneer VSX-D702s receiver - no sound - need...

Question

Hi there

my old Pioneer D702s receiver is out of order.

How it used to be:
I was used to hear a relais clicking after I turned on the unit. Once the relais closed/opened the receiver would work just fine. It used to take only a second or two until the receiver was ready.

How the problem started:
I noticed that my receiver would need more and more time to get ready. Sometimes it would take minutes until I heard a relais clicking. How it got worse:That relais click problem got worse. It would need more and more time. Sometimes the problem would even occur when I switched to another input source. I would have to wait for that relais again.

Today:Receiver turns on. I can select inputs and whatever but theres no sound.

I know that the modell is very old but I like it :) Could someone provide me with a circuit plan or service manual? Anyone having/had trouble with same modell? Thanks