Arpeggio UP/DOWN 3notes

I’ve been struggling for a while now with many of the different arpeggio patches. When Selecting Up/Down mode the organelle always seems to play three notes. For example if I hold down a high C it 2 1/8note high C’s then a lower C 1/4note. Again this seems to be the case in all arpeggios patches that have up/down but in this case say Arpeggio Synth patch.