Desperately Seeking Asterisk Savant

We have an asterisk install for about 10 extensions.  Our service is copper to our office and is provided by Grande.  For some folks in the office, about every 3rd call is dropped for no reason.  It hardly ever happens to some folks, but happens several times a day for others.  Sometimes the same extension will drop a call after 10 seconds, sometimes 30.  There is no rhyme or reason for it.  After reviewing the logs, it appears that a "hangup" command is coming across for an unknown reason.

Anyone out there brave enough to come in and troubleshoot this issue?  If so, please email me your availability and hourly rate.

Thank You!

Andy

P.S. HELP!!!!!!!!!