Ultrapitch octave glitch in playback

hello waves community

i’m new to ultrapitch and am using it on a vocal track, but it is having an intermittent problem on playback that is making the track unlistenable.

i’m pitching the vocals 12 semitones with a format shift of +3 to give it a female vibe, but every now and then it jumps down an octave, sounding like a bad adolescent cough. i’ve put a short clip online to listen to, but as this is my first post i’m not allowed to include it here, but it’s called ultrapitch-glitch.mp3 and is on my keef chemistry site, for those in a mood for hunting

has anyone come across this before? and more to the point, is there something i should tweak to fix it?

fyi, i’ve done a little pitch correction in flex pitch to get myself in tune - might this be affecting ultrapitch?

tia hive

prompted by waves support and having tried a few tests, it might have something to do with where i set the lower threshold in the pitch detector pane, so i’m not adverse to trying the plugin in another session to see if i can set it without incident.

seeing as this doesn’t appear to be a widespread problem it’s indicative of human error ; ]