Help needed: Lost audio in signal

#1

Hi,

My board lost Audio in thru the Jack input.
No vu signals in any of the audio in objects.
However, when disconnected from power I can ear the signal passing thru the board.

Any ideas, please?

Thanks

#2

something tells me it's a short circuit?
meaning that the signal is flowing trough the ground, which isn't good at all, and may damage the output of your connected device!

edit:
my suggestion is wait until the issue is resolved (what the problem exactly is) before continuing, as you don't wanna blow stuff up.

#3

Let's first eliminate the possibility that the input amplifier is configured to mute:
Put a audio/inconfig object in your patch, set gain to 0dB, boost to 0dB.
This is normally the startup default, but if there is a patch on sdcard or in flash memory that configures the input amplifier to mute, this setting is persistent as long as the board is powered.

#4

Hi,

After several "boot ups", updating the firmware and some disconnected time, it is working again. YES.
In fact, the audio in was lost and the global output volume was some dbs lower (by my akai EIE VU meters).

In fact, as @Inaba replied, i think it was some kind of short circuit, maybe due to my poor home electrical installation.
I can feel (shocking) some electric current passing thru the metal of some of the connected devices (computer, audio device, other synths, audio cables etc..) . Moreover, I did some soldering in the afternoon, in order to add some pin out terminal connectors to the board. Maybe some residual was in the board or something. I Was very afraid of damages :fearful:

BTW, @johannes, For the next version of the boards (I can feel that there are more to come :smiley: :D), please, please add some terminal connectors in order to avoid direct soldering in the board. For noobs like me, It will also avoid some heart attacks. :smile:

Thanks for the reply.

#5

I do not see how that would have helped, other than the input amplifier gain setting.
Perhaps, did you use headphone out (the mini jack) for anything else than headphones?

Bad switching power supplies inject current on the earth terminal. Chinese macbook power supply knockoffs are especially suspect.

The problem is that there are so many different possibilities: female header, male header, male header on the bottom, wire-to-board connectors, screw terminals...
Soldering is so much easier than desoldering, so I believe it's best to leave the gpio pads unpopulated.

#6

It must be the case. I've several suspicious power supplies and no earth terminal.
I'll change all the connections to a circuit with an earth terminal. If this happens again I'll come here for help.

Thanks again for the fast and helpful replies.

Cheers