4x4 Low revs power drop/surge.

Had to have the DRL bulb housings replaced under warranty today, (flickering bulb - known fault), and asked the dealer to check a separate issue we'd been having of late:

When moving off in 1st, the normally smooth pick up in rpm would suddenly stutter/hiccup for a fraction of a second, then return, making the car surge forward slightly.

All behaved normally at higher rpm in higher gears.

Dealer's mechanic experienced the same on a test drive and suggested using Maxidot to alert the ESP to the fact that winter tyres are fitted, (same size as OEM summer rubber, but slightly different Load/Speed rating), and so far, touch wood, I can't replicate the rpm problem.

Odd thing is I've never bothered changing the setting to winter tyres before and don't recall experiencing the same rpm issue in previous winters with the winter tyres on.

Anyone experienced similar?