New tyres, tracking or both?

[mork23]

I've noticed over the last few days I'm getting a rumble/vibration on the near side what seems like tyres.  I'm just over 10k with mainly motorway miles with plenty of tread left.  However, my journeys on a Friday always include a section of a couple of miles over those annoying sleeping policeman.  This no doubt has knocked my tracking out regardless (it did on my old MKII VRS TDI anyway) and the sound I now have is nigh on the same I had with that (never disappeared).  However, it tends to come and go over a period of several to around 30 second intervals on varying road surfaces and different speeds.  Could it be sawtoothing (I've only heard mentioned so not totally sure what to look for) or tracking or a combo of the two?

 

Annoyingly if the sleeping policeman are to blame I've no way of getting around going over them and I've tried the slowing down, two wheels over the middle and it's painfully slow.  :no:  Also, would doing this mean I'm wearing away the left side supports/bearings/etc quicker?  

 

Anyone else experienced this?  Recommendations?  I'd rather not fork out for new tyres when they're just below the 4mm on the front and oodles on the rear of the original Pirellis.  And tracking these days seems to have doubled in price in the space of a couple of years (£49 last time I was quoted!)

 

TIA