Anyone else experienced this... on odd occasions my Mak fires 2 balls at once. The first can usually hit the target fairly well but reduced power, the second is much weaker and quite visible in flight. I did not believe this at first but then started counting the mag shots and, sure enough, 12 trigger pulls emptied a 13 shot mag.
I am not sure if the first ball just sits in the front of the barrel with a normally seated ball at the top of the mag or whether the first ball fires as normal and the second fires on some sort of 'rebound action' from the CO2 moving the balls in the mag ... or maybe the gas valve is not closing as rapidly as it should.

Interesting eh??

Cheers, Phil