Knocking noise when hitting 80-90 mph???

[xxgem6n2xx]

Hi. I'm a new member and was wondering if anyone could help me out with a problem with my gti?
Its a w reg 1.6 gti and ive noticed that a knocking noise occurs from the front of the car when speed exceeds 80 mph. I've taken the car to a garage who checked the wheel alignment and the wheel balance etc which was all sorted but the problem is still there. It makes the dash shake quite noticeably. I'd be really grateful if anybody had any ideas on what it could be? Tjanks. Gemma

[alexperkins]

can you position the noise (left or right?)

[xxgem6n2xx]

It feels as if its more from the centre to the passenger side. Ive had the drive shafts checked for security etc though and they seem fine so i don't know what it could be. It will drive fine and then out of nowhere will just start shaking when its about 80-90 mph. Can't be right can it? Thanks

[chrischap2003]

Is the car standard?

[xxgem6n2xx]

Yeah,its standard-had no mods done to it yet