As stated, my blacksharks do not work at all without being plugged into an active charger. The lights that usually indicate that they have battery or are pairing do not turn on no matter how long the power button is held or how many times it is pressed. Even when I do plug them in and turn them on, they show up as off in Synapse 4. Additionally, I can’t find the serial anywhere on the underside of the left earcup.
All the text there reads as follows (with the numbers X’d and letters N’d out because they might be important)
X-X-XXX-XXNN-NNNN
CAN ICES-003(B) / NMB-003(B)
IC: NNNNX-XXNNNNNN
FCC ID: XXX-XXNNNNNN