The Click in Mixbus (OSX) randomly misses beats. I am currently using 2.0.2. I don't know if the same thing happens in Ardour. I will test that but once again I had to abandon using Mixbus because of a simple problem.
You should report such issues to Harrison, via the email address you will have got when purchasing Mixbus. Also, you are a couple of versions behind, so I would suggest you update and try again first.
Your subscriptions & donations are critical help that make it possible for full-time development of Ardour to continue. Your support is critical and much appreciated.
May goal US$4500 (US$54k/yr)
Subscribers 815 US$1993/month
Support Ardour, get free upgrades: pay $1, $4, $10 or $50/month for a year: