Problem with cam going bright/dark on NVR only

[trance]

I have a Hikvision 4MP IR Bullet (model DS-2CD2642FWD-IZS) recording on a Hikvision DS-7604NI/4P NVR. The picture flashes bright and goes dark every minute or so. Same thing at night with the IR on. This problem does NOT happen when I record to my PC using Blue Iris. I can literally pull the cable from the back of my NVR, just change it's IP address so Blue Iris can see it, making no changes to any other settings, and there are no issues. Anyone have any ideas?
I also have a Hikvision dome at my front door that I don't have any problems with on both recorders.

Is there a setting on the NVR that would cause the camera to do this?

I am totally fine using Blue Iris for my personal use but was thinking of starting a installation business and wanted to have different options for customers. I've had lots of installation experience but designing systems is new for me.

I uploaded a vid to youtube showing how the camera goes from light to dark..

 

[alastairstevenson]

The early firmware for the 4MP FWD cameras caused a 'flashing' problem - I'm wondering if this is the same issue.
Others may comment or confirm.
It was fixed by a firmware update.
What version of firmware is on the camera?
I tried a search but didn't find any of the posts I'm thinking about.

 

[trance]

thanks, that may have been it. I was convinced it was a NVR problem so had checked the NVR firmware but failed to check the camera firmware. I upgraded and so far it looks like the problem is gone. I will know for sure when it switches to night mode. Thanks again for your reply.