@EMPIRETECANDY
I do not have this option on my NVR5216. I only have Version, Disk and BPS. I was on V4.001.0000003.2, Build Date: 2020-10-10 . I have updated to V4.001.0000006.1, Build Date: 2021-07-09, but still not have the option.
I remember when I first powered the device on, it was loud as hell, but it settled down during first configuration options and was really silent.
They sold you a very old V1 hardware. The smart fan is only on V2 NVRs. The V1 was stopped production 2.5 years ago. Currently we sell are all V2.
Though the firmware can be updated from V1 to AI 4.0, but the hardware different, so that is why on your NVR not have the smart Fan.
Do you know what else was changed. Right now the NVR is very silent and I do not hear the fan at all. All options are set (Continuous recording, plus SMD)