Cgs synth

Last night I finished the Burst Generator, everything seems to work
fine except sometimes when I am switching pulses my Burst Gen will
automatically set off a series of pulses, this seems to only happen
once if the pulse rotary is switched after the manual trigger or trig
jack have been applied.

Anyone have any ideas, the one thing I was unsure of is I used a
Shorting Rotary, should I be using a Non-Shorting rotary, could that
be the problem...

Thanks
Chris