Arduino Uno disconnection from PC when running code

Hi Guys,

Just a quick question, my Arduino Uno 3 sometimes will be disconnected from the PC when I run the code. For example, in my code one LED will be turned on when I press a mini push button. The code is fine and so is the connection. However when I press the button I can hear the sound of disconnection of USB port from my PC (you know the sound when you plug/un-plug USB card into PC). After a second it will be automatically connected back again.

I only noticed this behaviour since I started to switch usage between the clone 'Funduino' and the real Arduino. I guess the +5V power is somehow suddenly cut-off and turned back on again in this scenario. Anyone knows the reason ???

Thank you very much.

Kind Regards, Jeff

It the button perhaps shortcutting something ? What if you press on the housing of the button ? or try to bend the board ?

Cheap boards have bad crystals, bad capacitors, bad soldering, and bad connectors. Perhaps the usb connector is barely making contact.

It is definitely not normal. If you are sure that you did nothing wrong, you better trow away that bad board.