Disable VAD with asterisk servers as clients!(Comfort Noise)

Hi is it possible ??

I have various sip trunks to other asterisk servers but now I get problems with the confort noise levels

11.5.3.3. Comfort noise support incomplete in Asterisk (RFC 3389)

is there any .conf option i can change on each of those asterisk servers
At the moment this really affects the sound quality going bad after a while…