disable call from mac ring

I don't know if this is the correct way to describe this or not... so here goes: a) I have an iPHONE, a MAC + Tablet. b) It is important that I keep my mac + tablet - attached with my apple id for other reasons. c) I also really like the fact I can answer my cellphone via my MAC or TABLET d) HOWEVER ... most often I leave my MAC + TABLET at home, and take my cellphone with me - when I am away from home - my MAC rings, and my TABLET rings - rather loudly according to "she who must be obeyed" Why: Because my tablet & laptop are often plugged in charging.- This is also bad - because when I get a "SPAM CALL" - my iPhone very nicely routes it to voice mail, but ... my Tablet and MAC ring at ear-breaking decible levels. According to "she who must be obeyed" violence upon my MAC + TABLET may occur if I cann't fix this. e) BUT - I do not want to LOGOUT of iCLOUD ... for other reasons above -- My question is this: I need some way to mute the ringing, or control the volume when I am not home. Or possibly turn this on - when I am actively using the computer, ie: with when locked - disable this.