There is a bug in some models of Uniview cameras in which, if the alarm output is configured as NC (in NO mode as default this effect does not occur), it is activated, it opens at 00:05.
This fault is solved with a firmware update of the camera. This update should be found on the Visiotech website in the product itself, in the download tab:
The models on which this effect may occur are the UV-IPCxxxxSS-xx-I0: