ICS L85 double feed

[Kye]

Could do with a bit of advice guys! Recently my ICS L85 has started to double feed, had it over six months and haven't had an issue with double feeding before. I'd say maybe 1/30 shots, so it's not often but it is happening.

I have recently switched to deans and I am using a 8.4V 3700MAH, but I wasn't having a problem when I first switched to deans, but the problem did start since I used a new better charger. I am wondering if it could be over-spin from the bigger battery getting more juice?

I have changed back to the stock bucking, so it isn't an issue with the bucking. I am wondering if maybe it's the tappet plate or the tappet plate spring? I haven't open up the gearbox yet so I have no idea what the condition of the plate is.

Any ideas would be great!