zgemma h2h cable hijacks router

hi i'm pulling my hair out have zgemma 2s in one room and blade 7000s in another both satelitte through vm router and both working great, but i decided to get a zgemma h2h with cable to get my hd channels back. set up box and it works great no problem until i went to box in other room and all the channels are scrambled i've checked ip address's mac address's everything seems ok but when cable box is on it stops the router signal to other room, but when i switch cable box off the signal returns to other room cant understand what i've done wrong or how to fix it. any ideas. cheers.

thanks for reply the boxes have different ip addresses one ending 2 the other 3 dont know how to check server details. thank you