Fiat Stilo 1.6 Active 3 dr wobbling/vibrating/shaking at 40-50mph??

Just bought a Stilo and it "wobbles" between 40 + 50mph, once you get past that it's fine, don't think it's a problem with wheel balancing, guy I bought it off said he was told it was prob the drive shaft but doesn't make much sense to me. I know the front shockers are shot, could that be causing it?