hi Seth
you make enable spanning tree on all network switch if you see same eror on your switches
you run protect-port command on edge switch.
stp some loops creations unaware ;stp trun of on switch bpdu packet dedect ,because not include bpdu loop packed on switch stp unaware this loop.And you see most excessive broadcast eror.
there fore you make on egde switch enable protect port command for other loops.
for example loop protect on 2600
2626(config)# loop-protect
disable-timer Set time in seconds to wait before attempting to
reenable a port.
[ethernet] PORT-LIST Specify the ports that are to be added to/removed from
loop protection.
transmit-interval Set time between packet transmissions.
trap Specify loop protection traps that are to be
enabled/disabled.