I put the first kit together last week. It appears to really "want" to work. It boots as expected, but no chime. Although there are a series of fast audio "pops" as the blue leds flash rapidly. There is no audio when attempting to play the instrument. At first I assumed that I have a cold solder joint on the board some place, but I have inspected them with a magnifying glass and a multimeter / continuity tester from the top of the pins or leads on a component to the edge of the solder pads on the other side of the board and get strong signal everywhere. The preenFM2 navigates as expected, USB drive is easy to access to load patches etc. Power seems clean on both USB connector as well as when I use an external power supply. I bought 3 kits, so I swapped out all of the chips in pairs and have gotten the exact same results each time. The Oled screen works great. I'm stumped. I ran continuity on all the pins of each socket to the edge of the solder pads as well, also clean signal. I double and triple checked the resistor values, polarity of the Electrolytic Caps and diodes, all seem ok.
Any ideas? Maybe I have missed a crucial step in the build? Pics are attached.