Does anyone know how to use two Tomy (non digital)monitors in one home successfully? I need to have one parent/receiver unit downstairs and one upstairs in the loft room and one baby unit with my toddler (can hear him from loft room okay but not downstairs without monitor) and one baby unit with DD (can't hear her from loft room or downstairs without monitor). Can't put both on same channel at the moment as that causes interference and one won't work. So I'm using two different channels and having to remember to take DD monitor to bed with me..ideally would like to run both off same channel - can it be done? I've been trying Tomy's careline but it seems that they don't (care) as they only have an answerphone and haven't replied to several calls made over the past week!