Multimedia USB port

[noidy75]

Hi All,

Can anyone confirm what voltage supply goes to the USB ports, i know output is 5v, just need to confirm if input is 12v?

I believe these are not fused and power supplied from headunit loom, I have had two of these fail on me so just wanted to check it isn't a supply issue.

Would plugging in the Fakra connectors whilst the stereo is on possibly blow the multimedia box?

Thanks in advance