R5 and Meike Twin Flash sync issue

Apr 29, 2012
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I have a Meike twin Flash that I like using for macro. It works fine with the 5D4 and R. But with an R5 I get a shutter sync issue where only the bottom of the frame is lit by the flash.

I initially had the shutter set to 1/160, so thought if I slowed it a bit it would fix the issue, but all the way down to a 1 second exposure I have the same issue. I've also tried going from mechanical shutter to electronic 1st curtain, and changing the settings on the flash.

Any ideas on how get this combination to work would be greatly appreciated.