Track control arm nut loose

[MACH1]

Took my Wife's A3 TDi 2005 in to Audi Stealers in Barnstaple, for a service,Expensive but car still under Warranty, They changed the track control arm, Been driving the car now for over a week and there is a Knocking noise from around the front wheel, I phoned them up and they said i would have to wait a week or so before they could check it out, I insisted that they need to check it out now and they gave me the number for Audi Assistance, they came out straight away and discovered that the Track control Nut was loose and about to fall off, I phoned Audi back up and they said pop in when i'm passing and they would have a look, I said no i want it booked in now as my wife is scared to drive the car now, The car is booked in now but they reacon that the nut must have come loose by itself, I went berserk and said are you telling me that a locking wheel safety nut can come loose by itself, if this is the case then you had better do a recall on all Audi's and get them checked out, His bottle went then and now i've got a loan car while they investigate why this nut was loose. Audi service?

[Mook]

I would suggest you put your complaint in writing to the service manager telling him/her exactly what happened and when - but keep away from slating them. At least the muppet who did the work will get a kick up the arse and they may look at their quality control procedures!