S2440L Weird Blinking Problem

Hi guys,

2 weeks back i got myself s2440l dell monitor.

I am having some weird issues with this monitor. Whenever i switch on my light or modulate my ceiling fan speed, the screen goes dark for 2 sec and reappears. This don't happen with all switches. Just some of them.

Does neone else facing this issue with this dell monitor??

Here's the link of the video:
*www.youtube.com/watch?v=RghO8gA__IA&feature=youtu.be