Quiet safe residential area near public transport? (Montpellier)

Hi there, I'm an Irish expat (based just outside of Paris), my husband and I are interested in trying to buy something in Montpellier for holidays/retirement etc... As we've just come for long weekends etc we are not too sure of areas: we are currently renting a holiday let for 2 weeks in Croix D'Argent and definitely don't like it, mainly due to traffic noise, noisy neighbours etc.. (we are spoilt in that where we live just outside Paris is VERY quiet)... I've realised that Mosson is to be avoided but would love any advice on 'safe' nice areas to look at on our next trip! thanks