«  Down to débalage! »

Pedal purchased and tested immediately: it is already difficult to insert without a battery screwdriver. After finally figured out how to open it (the manual gives little explanation) without destroying everything, first try. One of the LEDs does not light. So back to the store who wants to me to take another different brand. (Luckily I had not purchased online)
For 4 euros more I ordered the BOSS AB2 which only supports 2 inputs but that seems to be much more reliable.