121,000 miles on the clock. In the last few days, I have had a pinking
sound (the oldies will know what I mean!) Could it be the timing belt?
I have a Synergy 2 diesel tuner fitted, its on number 5 at the mo.
Maf boost low Hi torque Hi power, which produces no noise. If I put it
on number 10, MAF boost medium Hi torque Hi power, I get a pinking
noise. To be honest, I cannot tell any difference in performance with it
fitted  2013 Dynamic Santorini black
2011 XS Lago grey
2007 HLS Stornoway grey
sometimes towing an Elldis AVANTE 574.

on a diesel!? , as an oldie, I only ever experienced this on petrol cars - usually timing or mixture 

You can still get pinking on a deisel infact it can be worse. Just had mine remapped and it pinked like mad. It was running far too lean. Had it remapped with my original software and its stopped. The higher the settings the more chance of pinking as diesels combust at a higher rate, hence the pinking