NAD 3020A transistors heating up.

[bmmach]

Hi all,

Still learning my NAD 3020a amplifier that I recently acquired. Everything seems to be working fine but I have a concern on the phono section.

My phono section has 2 pairs BC559B ( Q409,Q411 and Q410, Q412) that seem to be getting very hot even when the phono section if not in use. After about 5 minutes from switching on, they get quite hot to the touch, while all other semiconductors are just warm.

I have attached my Circuit diagram for help in troubleshooting.

I have looked around with a multimeter and can confirm that all the components seem to working just fine - no major departures from the circuit levels. I have fully re-capped the entire amplifier too to eliminate the electrolytic caps problem.

I need assistance to help diagnose the problem - unless that's how they are supposed to run.

Rgds