Weird issues with analog inputs when headphone jack is unplugged

Hi! I’ve been posting about this on the Discord a little but I figured going here would also be helpful!
My current issue is I have a joystick (effectively just two potentiometers) hooked into two analog in pins on the Daisy. The issue is when I unplug a headphone cord from the jack it causes the joystick to stop responding and seems to just rest at a steady value about halfway between 0v and 3.3v. Also sometimes the audio jack can be fully plugged into a device and the joystick will still not function. To be fair I think this may be that one jack is a mono input whereas the other is stereo. However, I am not sure. I have it wired (with the socket facing you) Left - Left Channel, Center - Ground, and Right - Right Channel. The audio seems to come out just fine, so I don’t know. The buttons I’m using also continue to work, albeit those are running off digital reads so I’d hope that they would. Here’s a (admittedly very poor) schematic of my current setup:


I should also note that this is not the first time someone has seemingly had this problem. This post here almost directly reflects my exact problem:

I did end up contacting the poster and sadly he hasn’t found out anything since to help him. So, I suppose anyone willing to help would be doing both of us a MASSIVE favor.
Huge thanks in advance and don’t be afraid to ask me for more clarification!
P.S. Here’s the audio jack in question that I’m using in case that’s of any use: Amazon.com

The Analog to Digital Converter inputs reference to DGND - not AGND.
AGND should only be used as reference for the audio inputs and outputs.

AGND is not connected to DGND on the seed. R7 is a 0 Ohm “DNI” (do not include) resistor on the schematic.

I guess when there’s a audio cable connected, there’s a (relatively) low impedance connection through the analog ground on your audio output - through your audio interface , through the usb connection back to the daisy digital ground.

Use “DGND = pin 40” and “+3V3 digital = pin 38” for the joystick.

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Thank you SO much for your very specific and technical response, genuinely!! I’ll give it a shot tomorrow :slight_smile:

I’m not sure this is the 100% correct answer though.

On the schematic for daisy patch, the seed AGND is connected to DGND on the patch PCB.
image

Their input pots use +3V3_A (analog) (NOT +3V3_D (digital))

I would use 3V3_D for the pots.
But another option is to connect AGND and DGND, and keep your other connections as is.

Perhaps someone has a link to a good explanation on what’s going on.

It does seem to be best practice to connect analog ground to digital ground from what I’ve heard/seen. I’ll try it tomorrow and get back to you with my results.

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Can confirm connecting AGND and DGND is the proper way, my issue was that they accidentally were not connected on my device. Apologies if I caused any confusion.

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