Thanks again for your help.
I'm already using your settings for Mgcamd emu.
Yes, that's what I meant - Mgcamd emu with Newcamd protocol is what I'm using normally, but I will see if changing the protocol to Cccam will improve channel zapping (I also tried using Oscam emu but wasn't happy with its performance).
In general it's not that slow (although it's slower than it was a week ago) but there are certain channels (i.e. Eurosport 1 & 2 HD PL) that take 5-6 sec to start.