Fenix L1P flickering...ground problem?

One night my L1P went dead a split second after I clicked the end cap button. Of course what do I do but turn it around, look right at the LED and it turns back on, blinding me... But I digress...

Anyway, in the past couple days it's been flickering. I read through the forum and found a lot of people have problems with the tail cap and that I could ground the battery to the body to bypass the tail cap. Well that didn't work, it still flickered.

I unscrewed the head from the body and found dark stuff around the edge where the head contacts the body. I assume the grey stuff is epoxy, but I'm pretty sure it's not supposed to be on the copper color edge as that is the area that electrically contacts the body. Also, on the body side of that interface there is some gray residue.

I semi cleaned off the contact on the body side and it seems better now (we'll see how long that lasts). I'll take some sandpaper to it later. Do you guys have this same contamination?

Head side of interface:


Body side of interface:

Mine actually has solder at the joint where yours has the epoxy. Mine started to flicker once but I just tightened the tail cap and had no more problems.

I know this may sound a little wierd, but I just want to make sure just in case. If you have taken it apart recently, I would make sure that you have the body turned correctly. A problem with the design is that its can be hard to tell front from back. It is easy to re-attach the body backwards. This has been know to cause flickering.

As suggested above, the first thing to try is to tighten the tail cap switch by taking off the tail cap and using an appropriate tool to screw the inner ring (the one with two holes) in a little tighter. Sometimes it tends to loosen up over time, which can cause the flickering. I had someone hold the tail cap for me while I used two awls (one for each hole) to tighten the ring. Worked good and solved the problem.

No I have never taken apart the front of it and I've had it since Nov of last year.

Also, it can't be the tailcap because I bypassed it by shorting the battery to the body and it still flickered.

Mine started to flicker, I just cleaned the surfaces with alcohol that came in contact between the body tube and the head also the tailcap,
no problems since