problem madamp G2

Hi,

I built a madamp G2, i haven't got much experience like my english...

Here's my problem, i turn the volume on ,it's ok but when i turn the tone on the sound is nearly off and when i turn on full tone, i've got a bad saturation and the sound is down.
i take the measures.
V1
pin1 163v
pin3 1,5v
pin6 162v
pin8 1,5v
V2
pin6 237v
pin8 5v
For information i use speaker musicman 8ohm 50w or 65w for the moment.
What's direction to find my problem?

Thanks a lot
franck