Can’t comment without a representative recording.

Are you asleep when you get the big percentage? I get ‘other’ a lot when I’m asleep and rate goes low.

If that’s the case I suggest you consult an Electrophysiologist.

It coudl be a noisy signal – I haved found that my % of ‘other’ goes up when there is noise on the recording. I have tried everything to reduce noise – sonogel for the contacts, anti-static spray for my clothing aroud the monitor, but the best approach I’ve found is to wet the contact areas with some saliva before putting the monitor on – it seems to have the right amount of condcutivity and stickyness to keep a good contact throughout exercise !