Misfeeding

Most likely the bucking is upside down. Sometimes I still install my buckings incorrectly in the hop up chamber. Typically upside down, which causes double feeding, and sometimes misfeeding as well.

Should be making a "pff" noise like a quiet ol' fart (different than the sound it typically makes).

Well if the echo 1 is modeled after the sr2 then you can get all kinds of parts for it here is a link to x-fire just scroll past the type 96 parts, http://www.x-fire.org/etop/t96.html .

Just got a new bucking, ordered it

Becareful when you give advice on the ASR. It is a collection of parts from different guns.

And it isnt an APS2 on all counts.

The hopup chamber is a type 96, not an APS2.

If and when the OP has the money and desire, you may want to get a PDI hop up chamber and AEG barrels. On mine and a few others that I know of, the hop up arms on the original chamber broke in several places. Be careful.

Thanks Ronin.
I am looking into PDI, but, i need the cash first.