I am now not getting any sound from the stereo jack. It was working in the begging, but all of the sudden now no sound. Any advice why or how to check if the output is working or malfunction? Weird that it just stopped working.
Unit powers on, blinks 3 times, and triggers - not sound from jack. 
Check the solder points, try a different cable/set of headphones, etc…that’s not expected
Solder joins looks fine, and tried different headphone - no sound. I use a Picoboo trigger that sends a 12V current to trigger - not sure if that overloads the board? Although it does power up and triggers just now sound.
thx
Where are you sending 12 volts and what board are you sending it to?
Sending it to the ground and first trigger are use a 12 V trigger to trigger other prop components
Sending it to the ground and first trigger are use a 12 V trigger to trigger other prop components
?