When testing some of the firmware on the Trinket Pro side I noticed that my button IO was a bit slow. I was using a 0.1uF cap (cap code 104). This gave me (according to the MC14490P datasheet) a debounce rate of ~15Hz (at 5V). If I use a 0.001uF cap (cap code 102) the debounce rate of ~1.5kHz (at 5V). This is much better. It took me a while to figure this one out. I must have looked over the data sheet at least a half a dozen times before I found the debounce rate calculation. If I had a scope, I would have easily been able to connect input and output sides and determine the debounce time / rate.