@JohnTricubik Thanks for the feedback.
I don't think it is a debounce parameter issue. It is hard to tell if you are actually firmly depressing the button or just bringing the keycap to the button. There is a gap between the keycap and the button so if you lightly depress the keycap, it will touch the top of the button and not "make" the switch. A keypress needs to "bottom out" (travel no further) in order to make the switch.
We have a low travel, silent version of the Twiddler. Actually the first batch was made this way. If you know someone with a Twiddler with a serial number <100 give it a try. Here is the difference:
There are two sets of keycaps: the rows of AB's and the rows of CD's. There is a plastic spine that runs horizontally between the 1st two rows of keys and the last two rows of keys. Each key is connected to one of these spines. They keep the keycap perfectly aligned with the button and they hover about 0.010" above it. This makes for a very short travel and super quiet keypress.
During production though, we found that, in some cases, due to that variability of the plastic injection moulding process, some of the keys could stick a little making keypresses difficult to detect. We test each and every Twiddler twice before shipping it. During the final test we were noticing a low acceptance rate due to "sticky" and non-travelling keys. So, in order to lower the attrition rate, we cliped the keycaps off the spine and let them float on top to the button. This gives key keys the feel you have now.
We still make the Silent Twiddler3 (Twiddler3 S, i suppose) on request. I have a demo unit that can be shipped out for evaluation, all we ask is that you pay for shipping back to us. If you are interested open a ticket at Tek Gear Support indicating your interest and we'll start the process.