V8 Disco 2 intermittent misfire

Started about 3 months ago, engine would cut out when stationary, say at traffic lights.
At tick over in drive on autobox the engine revs would fluctuate and sometimes the engine would stall.
At normal speeds it is fine except for sometimes it will hiccup but only on idle throttle for example slowing down in traffic.

I checked out the autobox and had fluid changed: no difference.
Diagnostics pointed to Idle Air Flow meter, so that was cleaned and things improved a bit but still not right.
Couple of garages and a main dealer had a look but couldn’t pinpoint the problem … only advice was to change bits until the problem goes away.
So I bought a second hand Idle Air Flow meter and fitted that but still same sort of problem.
Replacement MAF …. But that does not seem to work at all (right part number but when I put a meter on it is shows output out of normal range … should be 0 to 5v … this thing is returning 10v).

Btw. It is dual fuel petrol/LPG but problem is the same on either.
Any ideas?

Help !!! .... someone must have some ideas, I am running out of bits to try to replace

I get the fluctuating idle sometimes as well. I normally put it into neutral and hold the revs at 1500 for a few secs and this will normally bring it back in line. It only seems to happen on mine if it is hot in slow moving traffic or I have slowed down suddenly after a high speed run.
was it a genuine maf? I have heard that the cheap (non bosche) ones can give false readings also the ignition system needs to be tip top . plugs leads and coil pack

have new MAF on the way (genuine part from main dealer) ... will report results

New genuine MAF now fitted, a week of long and short journeys ... and all the problems seem to have gone (touch wood).
Hell of a thing, diagnostics didn't point to it, the symptoms could have been caused by anything connected to the ECU.