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#206701
Here are 2 drawings illustrating the schematic. The first picture shows the connections between the WAV trigger and the touch sensors (not including the LED pins of each sensor - that is on pic #2 which hopefully will transmit even though it's not letting me add it as an attachment for some reason)
Apologies for the rudimentary quality, I don't have proper schematic-making software!
WavTrig Schematic 1.jpg
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#206773
wavtriggerSchem2.jpg
There we go. Okay so this is the LED circuit using an IRLB8721 MOSFET and running each out pin through a diode at your recommendation. The whole kebab works for a short time and starts glitching out after not very long. What happens is the touch sensors begin triggering on their own. I thought using the diodes would help that but perhaps I need a different diode?
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#206803
I really can't say for sure what's causing this, but my theory is your LEDs are drawing more current that the 5 volt rail on the WAV Trigger can supply. The symptoms you're describing sound like the regulator heats up due to excessive current then begins cycling on and off to reduce heat. I think that's what's causing the glitchy behavior of your touch sensors.

I'd recommend trying the sensors and LEDs on their own separate 5 volt power supply and see if that does the trick. You would need to connect the ground (negative)on both power supplies though.
#206936
I think the problem lies with the touch sensors because I removed the entire MOSFET + LED portion of the circuit and still seeing glitchy behavior on the touch sensors where they are constantly triggering some kind of sound. As soon as a sound clip finishes, all 4 sensors light up and trigger a sound until there's no sound being played, and they light up and trigger again without any touch input. I tested the entire proto board for shorts and found zero...
A few things I've noticed is the touch sensors activate on lift-up instead of touchdown. So there's been some kind of polarity inversion... or I guess they need pull-down resistors but I didn't have to do that in the past with these sensors. Also when I'm not touching the sensors, they are dimly flickering.
I'm very confused :(

I did rig up the MOSFET + LED circuit on its own proto board with an Arduino Uno and am using a very basic code to fade the LED array up and down. This was just to be sure that portion of the circuit was indeed working.
#206938
I checked the hookup guide and am seeing that the "LED enable" joint should be desoldered to control the LED separately, so I did that for all 4 sensors but still seeing glitchy unstable behavior. Did I mess up these 4 from all this tinkering? I have a bunch of spare touch sensors, but at $7 a pop, I'm hoping not to need all new ones.
I feel like pull-down resistors are the way to go. I will explore the user guide and datasheets more deeply but some of it is over my head.....