Cubase 5 odd problem

Hi, wondering if anyone can help.

I’ve got a project where i’ve got lots of Audio tracks and two VSTi’s, both being EZ Drummer, one being a normal kit and one being percussion.

For some reason I have a few “phantom” tambourine hits on my drum track. I can hear them when I solo the track, and can’t see the hits in midi editor.

I’ve never had this issue before.

Any ideas?