Wandering Passat B5.5

I have a 2004 TDi Highline.

Issue is the car will not drive in a straight line. Needs constent attention from driver to just keep within the lines on a motorway carriageway.
points to note, changing shock absorbers all round has not resolved issue.
New tyres all round (All Dunlop BluSport) has not resolved issue.
Tyre pressures are as per handbook and are regularly checked.

Car has been into a garage and wheel alinement checked. All found to be okay.

Any ideas would be greatly appreciated.:1zhelp:

worn bushes or bush or balljoint on front suspension.

Thank you. I will check them out.