Tccl — Replaced Set Top Box ISSUE

I have recently replaced new set top boxes 2 nos. for my house with TCCL Classic HD pack however for my ground floor house when I use set top box it seems display goes and comes when I switch on other electric appliancw with ceiling fan. I have checked with my electricity with the help of electrician for my ground floor and also I have checked with my another TV with same STB as well as alternate STB under ground floor it seems same issue display goes and comes when STB is powered. My home electric supply, TV and All other appliances looks good and it seems thers is a problem with the replacement set top box. The same I have updated with my cable TV operator. This happens due to heavy signal dropping from your main end and it's bugging up my TV. As I got two STB's under my mother named Kamala.K. My both the TV display goes off and comes automatically by using both the replacement STB's in every 4 hours with both normal and HD pack channels with or without switching on other ceiling fans. So, kindly look into this issue very urgently and do the needful otherwise I have no choice of switching to other dish TV network.