EOS RP flash sync issues beyond 1/180

[Crey23]

Hi all,

I was recently contacted by an IG eos RP user regarding this issue and I tested it out today, and realized I too have this issue in my RP.  I was taking pictures with off camera and on-camera (external) flash, and any image above the 1/180 sync speed you can see the at the top of the image the black banding from the shutter.  I took it to 1/4000, and it was noticable in nearly all but one of my test shots.  I have two cheap speedlights, a Yongnuo YN568 EXII and a Neewer 985C, both have this issue, but it's far more noticable on the neewer.  The IG user who contacted me is using a Godox TT560.

Now, I know these are not canon speedlights...but I never had this issue in 650D/(T4i) while using the speedlights (both cameras max at 1/4000 shutter speed).

Could this be an issue of the t.1 power rating?  But if so, why at equal settings this is not visible in the 650D (T4i)? 

Could the lack of mirror have the sync trhown off?  maybe faster now without the time of the mirror to flip?

Anyone else experiecning this?

lastly, I would not presume that the 1/80 sync speed in the camera would be affecting this correct?

Thanks in advance! 

[onavarrette]

Hi!
I have a Canon RP and a brand new Godox MS300 flash. When I set the shuter speed to 1/200 I start see it a black line on the top of the images.
I check the firmware version and I had the 1.1.0
I update the firmware to the lastest today 1.6.0, but the problem persist.

If anyone had any clue or suggestion on how to fix this error to be posible to use my Canon RP with a 1/200 speed and a Godox flash would be great!

Thanks