Strange sound beneath the seat when charging start

[plukcc]

When ever i start charge the battery
Strange sound (like insect) comes out from beneath the passenger seat
I can email u the voice file as I have recorded it
I can't hear it once the fan turns on

[frodus]

Probably the switching frequency of the charger. If you have noisy power coming in, it will be worse. Pretty normal, but if you could record it and post.... that'd help.

[BrammoBrian]

Probably the switching frequency of the charger. If you have noisy power coming in, it will be worse. Pretty normal, but if you could record it and post.... that'd help.

I agree with this diagnosis.  If it's a "popcorn popping" or static-like sound, it's the audible switching frequency while the voltage is relatively low.  My bike does this as well. 

[plukcc]

It likes the insect high pitch sound
May I have an email that I can send the file
Tks

[frodus]

You can upload attachments

[plukcc]

Stupid iphone can't select sound files