This firmware version also triggered the algorithm error going from the 05-21 firmware to this version. And this is the official Dahua firmware; so I'm not sure what exactly is happening. Something doesn't agree
Did you lose IVS with version V2.800.0000000.1.R? I have IVS problems with the T5442M-AS, and this is the version that has the best IVS detection, for me. The latest available version is V2.800.0000000.10.R, and I'd think that's the one you'd want to try first. I'm currently using V2.800.0000000.8.R, which seems to be the least of evils in my camera. I'm seriously suspecting that not all of the 5442s are the same.