Credo 50 keep busy after using high shutter speed

[Sancoyo]

I am using credo 50 with phaseone 645DF+
Everytime I use shutter speed 1/1000 or faster the back just freeze, the green light blinking and at the bottom of the lcd there is a shutter icon with a running time lapse. It is as if the system is dumping its buffer to the CF card and everthing else have to wait. I waited until 5 minutes and lost patience, the shut it off.
If I use slower speed, there is no issue at all even though I repeatedly shooting as if in a burst mode.
Any help is much appreciated.

Sancoyo

[yaya]

Hello Sancoyo, please contact your deal or Support with more information e.g. firmware version on back/ body, lens model used etc. https://www.phaseone.com/en/SupportMain/ContactSupport.aspx

BR
Yair