UE Megaboom 3 Party up not working?

I just got 2 megabooms and alone they work great. When I party them up and put them in different rooms they crackle and cut out. They're only about 30 ft apart. Is this normal or should I return them?I just got 2 megabooms and alone they work great. When I party them up and put them in different rooms they crackle and cut out. They're only about 30 ft apart. Is this normal or should I return them?