Logic Platinum Midi Communication, Random loss of MIDI I/O Options

[smplfly]

I run Logic Platinum in OS X on a G4 800. My MIDI I/O is a MOTU MicroExpress.

I start Logic and both of my MIDI inputs work fine (a keyboard and a drum trigger). MIDI data is recorded as usual. But I'll pause for a while to program a patch or read a manual, and the next time I hit record no MIDI data is recorded. The MIDI input monitor shows that nothing is going in, but the data already there still plays my synths.

If I quit and restart Logic, all works again.

Any help would be appreciated...

-Smplfly