If I remember correctly, extreme power dissipation (6-7W I think) without cooling was the cause.
Anyway,I'm sure Rufusbduck's problem is ntc-offtime cap short,because symptoms match theory perfectly.
You nailed it. Not a solder short but a single strand of the ntc didn’t go in the hole. You can see it here sticking up from the base of the black wire like the boner that it is. Couldn’t see it with a naked eye. 
Fixed that and then toasted the op amp trying to test it with a 6V battery and test leads. I’ve got a new op amp on it now and it seems to be behaving but I can’t run it full power for long without the led in the light and that means re potting, re installing, and re crossing my fingers.
Nice find and fix RBD. Fingers crossed.
All 9 of ’em. 
I’m lovin/hatin this light more each day. Like bad hair, it grows on you.
@led4power - Bravo! Those are some excellent deductive reasoning skills. You certainly know your product well.
Any idea why the light flashes approx 5 secs after switching on high? It flashes 4 or 5 times then steps down to low.
Xhp70, 6 amps. The other driver worked fine but for the fact I messed up the soldering and it only had one mode so I changed it.
I had a similar problem Here
Possibly a short with the NTC
But got it working fine after cleaning each solder joint up
Sounds like lvp kicking in. Enough contact to work but drops enough voltage to register too little charge. Could be marginal contact in switch or tube/brass retainer contact. Maybe shim the switch 1/2 mm so it’s retainer makes better contact with the battery tube. Also, 6A is a lot of current and pushes Vf up high so any cell not high drain will both sag quickly and not run long. Even a high drain cell won’t run for long on high either.
5 blinks is low voltage warning,stage 1(<3V,or <6V for 2S);that usually means you have bad connection somewhere,ground path is mostly source of problems.
It was lvp, thanks for the suggestions guys.
Funny thing is that it was flashing in two modes but the third mode didnt. Then the third mode started flashing also so I thought it was a heat issue.
Flashing probably didn't occur in the lowest mode,because voltage drop/sag was lower than on mid/high mode,so driver was at 3+ volts.As battery discharged, voltage dropped low enough,so that LVP activated also on low mode. All this is completely normal behavior.
Now getting 2 mA, 12mA, 1.2A, 6A. Still takes a quick tap to change modes but is unaffected by heat. 6V and moon kits but moon has 3V resistor. Still, modes are very nicely spaced.
I mean user activated modes or groups, not the output level of low med high, sorry for not being clearer. The hold button for 15 seconds modes.
Ita thw first time I have ever hit lvp on any torch so hence the question here. I did look through thw info thread first but couldnt find anything. Thanks once again guys
I assume you mean 20mA,120mA on low modes?
I hope you didn't seal driver yet. Could you check resistance between GND ring and point 2 in this picture?
Sorry, that’s the buried side in the pill. Just one larger via in the ground ring at the sense resistor would make it vastly easier to ground this driver. Solder bridging is a pita to do/undo as you have to heat the whole pill instead of just a wire pad. Mode changes do work now and are unaffected by heat but just require a brief button tap so not sure if it’s worth cooking the pill two more times. At 6A and 6V this led produces a ton of heat very quickly and I’m not set up to test it adequately heat sinked anywhere but in the light.
Hello i was wondering what your thoughts are with respect to using the LD-2 with a triple 219C and a single 18350 or 18650 cell. Do you think the driver will overheat ? Has anyone tried this ?
As far as I understand, special care must be take when using a LD-2 with multiple LEDs (i.e. putting the FET on another a separate board). Using a triple 219C only makes things worse because of the low vf.
I have been running several lights with LD-02’s at 9A and 12A with high drain 18350 and 18650 batteries and nothing other than a good thermal bond to the light around the perimeter of the driver with 3x XPL HI’s and have not had any issues (yet) . I am concerned about the Lower vf, I might have to just try it and see what happens :)Is there a different driver that would be more suitable ?
Oh that’s awesome; thanks for the info. I didn’t know a LD-2 could handle it without mods. I think a regular FET or FET+1 driver is better suited for use with multiple LEDs though. I’m sure led4power will chime in though.
I believe the FET can be remote mounted on any XML mcpcb if the trace is cut between the gate pin and the ground pins. Alternatively a piece of copper sheet with a tab to solder to either the ground pins or the drain tab to pull heat away works.