Possible Interference problems ?

I run a wireless network (Cisco 340 Access point and both Cisco 340 and
other vendors' PC cards) in my office.

Most of the time, it works great - no problems.

Sporadically, it will take "hits" from 5 seconds to 10 minutes where the
clients cannot communicate with it (tested by pinging). Today it
disassociated everyone on the network for 15 minutes.

I am guessing that this is some kind of interference from someone else in
the building/area, but am clueless as to how to diagnose/prove it.

I am thinking about changing the "channel", but am not really sure what
effect that would have.

Can someone point me to some good docs or something ? Offer advice ? The
Cisco docs are useless.

Thanks in advance

--
JIM MATTHEWS
Dallas, Texas