Synth Plugin Arp Playing Extra Note

Hello Everyone,
I am not sure if this is an Ardour bug, plugin bug, or a JACK bug. Either way, I am a bit stuck troubleshooting this one. I have an Arch Linux install and an Ubuntu install of Ardour5 and I am trying to use the Helm synthesizer Arpeggiator. I have it set to play quarter notes at 120 BPM, 4/4.

The weird part is on my Arch installation the Arp is playing 5 notes (one cutoff) instead of the expected 4. Ubuntu is working fine.

I have used MIDI inspectors, and it looks like both systems are sending the signals at the correct time.

Does anyone have any idea where I can go to continue to debug this?

I have two videos to contrast the behavior I am talking about.

Appreciate any help!

This was discussed on IRC, I thought, by you and rgareus?

Yes, the IRC discussion came after this forum post and resulted in