Help-E2DL/VG-2 Bad (Random Output Changes), but E1B/VG-1 Fine

Folks, I picked up an E2DL yesterday. Could not wait to try the head on my Vital Gear 2 cell body. But when I did, regardless of how tight the head and tail cap are, the output somewhat randomly toggles between low and high output. I also learned I can reliably change between the two with just a shake! Running Surefire batteries. Could it be the batteries are temporarily losing contact, causing the circuit to think "time to switch"? The VG-2 body and switch work flawlessly with my KL1 and KL4 heads.

When I try my E1B head on my VG 1 cell body, it works flawlessly too, and this is my 2nd favorite EDC configuration.

I much prefer to carry bezel down and was hoping to use the VG-2 and E2DL head for my "perfect" (for the time being...) EDC. I'm now disappointed.

Any suggestions? Thanks....Jeff.

The problem sounds to me like the head and body are not making good
contact.
Try cleaning the top of the body at the top edge of the threads.

Thanks TX101. Cleaned contacts, though they were shiny and new. I've eliminated the random switching by tightening the head and tailcap onto the VG-2 as much as possible. I also tried to stretch the tailcap switch spring out a little. I seem to have eliminated the random switching, but still get an output change when I shake the light or strike the bezel in my hand moderately (i.e. if I use the striker bezel!). I seem to feel the batteries moving around when I do this, so I'm wondering if they are breaking contact temporarily.

Any further ideas on how I can prevent the unwanted switching or tighten up the insides?

Thanks....Jeff.

I have a light that the batteries would rattle inside the tube. I folded 2 seperate pieces of masking tape(2''x5'') in half long ways so I can use them again and slide them inside the tube along side the batteries.No more rattle.
As far as what you are expieriencing,I have the same problem with a KL1 head. It will work on the E body,the Aleph body,the Nitecore body but only sometimes on the VG1. Too bad VG FB1's are my fav.

Why the VG body? You can buy the clip from the E1B from SF and it'll fit on the E2DL (I think?) for bezel down carry. I'd personally also get rid of that tailcap for a regular Z61 clicky but that's just me. Otherwise, why not just use the stock body?

I like a deep pocket fit, bezel down. But I also just bought the E1B. I just looked at the E1B, and the clip mounts in the usual place at the bezel. If placed on the longer E2DL body, there would still be almost two inches sticking out of the pocket.... Is there an aftermarket SF retrofit bezel down clip?