Polygonal tyres

[MalcQV]

Thoughts please.

I have repainted my wheels on my daily Alfa GT and whilst all the wheels were off I swapped front to back. Now I have had the car for just 12 months and the original rear tyres (now on the front) were quite new when I bought the car. I have replaced the original fronts (now Falkens).
So my current setup is Goodyear F1 Eagles on the front (were on the rear up until Friday last week) and Falkens on the rear.
I went upto Leeds on Monday night in the GT to get some eBay wheels for the A4. I noticed almost straight away a rumble/whine like really badly worn wheel bearings.

So last night I took one of the wheels off the car to see if maybe I had distorted a back plate or something. Nothing catching and the wheel rotation felt very smooth and no lateral/vertical play so I did not suspect a bearing. I then checked the tyre..

If you look at the last block you can see flat spots. Basically the tyre on the inside edge is polygonal and there are about 20 regular flat spots.
I have read things from speed bumps to worn suspension components. I doubt there is any adjustment on the rear suspension on an Alfa GT.
One last thing, I have recently replaced upper and lower front wishbones and drop links but note that these tyres were on the rear and not the front. Though somewhere I read badly aligned front suspension can affect the rear. I am going to get 4 wheel alignment before the car is used again properly.

[zollaf]

knackered rear shocks ?