Beeping problems with my phone - not...

i recently purchased a phillips CD130 land line phone set - 2 handsets and 2 base stations. When i am talking to someone on either hand set - i quite frequently get a beeping in the call - the person i am talking to cannot hear it but jsut hear a gap in my speech. I'm pretty sure this is not an indication of another call coming in - but if it is - is there a way i can turn down the volume of this beeping. Also - the smaller base staion and the hand set that we have in an upstairs roomm - ocassionally just beeps for no reason while it is on the hand set - and keeps doing so for a short time then stops - they are about a couple of minutes apart. It just starts up and keeps me awake or wakes me up!! very annoying.