DTMF
Detection
relaxdtmf=yes
http://wiki.sangoma.com/wanpipe-linux-asterisk-appendix
Crackling
when speaking
http://tinyurl.com/6lnwz6
Static on
Line
pci=nommconf
http://tinyurl.com/5lvzr4
WAN Router Commands
http://wiki.sangoma.com/wanpipe-wan-operation#Commands
Fixing Echo - Sangoma Wiki
http://tinyurl.com/6yrj3b