[Asterisk-Users] Comfort noise support incomplete in Asterisk (RFC 3389). Please turn off on client if possible. ???? Xlite

[Ronald Wiplinger]

If one of my users call with its xlite client out via voipdiscount, I 
see in the CLI following message:

 Comfort noise support incomplete in Asterisk (RFC 3389). Please turn 
off on client if possible.

How can I turn this off?

He also complain that than he hear nothing at all.

bye

Ronald