Hello Grant and welcome to the Cow Audio Forum.
Thanks so much for bringing this issue to the Cow and letting us thrash it out with you.
That you were able to have sync for that long with your set up, I find unusual, damn lucky and good for you!
What’s changed? I like the idea that an unintended menu flip did it. Can you reset the camera to it’s original settings? (noting the customs you have made, so you can get back to them.)
Could also be that, over time, the values of the circuitry of your two clocks have shifted a little.
Please do keep us in the loop as you discovery continues.
Regards,
Ty Ford
Cow Audio Forum Leader

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