A/B Switch Box Pops When Switching

[ea26_rvt]

I built the A/B Switch Box kit from General Guitar Gadgets tonight.  I tested it first by using it to switch between two channels of a tweed deluxe-type amp.  Then I tried it switching between two different amps.  In both cases, there's an audible pop when switching.   Is that typical?  Is there a fix for it?

Thanks

[GibsonGM]

Post a link to the schematic so we don't have to dig around finding it.
Does it have pulldown resistors? That helps.

[ea26_rvt]

Thanks Gibson.  Here's the schematic. . . .

http://www.generalguitargadgets.com/pdf/ggg_sw_ab_sc.pdf?phpMyAdmin=4a28f86a515b7883e7bc35a68d4e7b6d

[Philippe]

Suggestion: Use larger value resistors (e.g. a 2K & 10K) on the LEDs.

[ea26_rvt]

OK.  Thanks. 

The pop is still present when the battery is removed and there's no power for the LED's.  Does that tell me that the LED's are not the problem?