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Soo, I got some issue with digital potentiometers....
Quote:

<Sorunome> well, it should be simple
<Sorunome> the thing is i have my sound mixer with feedback loops and op-amps where i had normal analog potentiometers then to regulate the sound level
<Sorunome> and now i set the digital potentiometers to the exact same resistance, i measured it, it is the same, +- 0.04kohm, but with those attached there is no sound output at all while it works with the analog ones fine
<Sorunome> usinc MCP42010
<Sorunome> oh and the potentiometers are all 10k ones so that +- 0.04k is almost nothing, the set value is 3.4k
<DrKerm> Hmmm.
<Sorunome> i mean, i even measured the resistance, so it makes no sense to me
<notipa> any stray voltages around?
<Sorunome> just measured - 0mV, so none
<DrKerm> 0mV is suspicious.
<Sorunome> on the digital pots when unplugged
<Sorunome> also now suddenly i got some sound - extremely quiet in the bg
<notipa> how well do they handle the voltage and current the sound thingy provides?
<Sorunome> idk on the channels they worked, only on the master it started iwth that stuff
<Sorunome> can't find anything in the datasheet D: http://ww1.microchip.com/downloads/en/DeviceDoc/11195c.pdf
<DrKerm> Sounds like something topic-worthy to me at this point.
<Sorunome> wtf the voltage when plugged in for hte analogs is 2.6V but for the digitals 0.6V
<Sorunome> about, changing all the time due to it being a sound signal
Provide a schematic or something. Guessing will get us just-about-nowhere.
Oh, yeah, sorry, the schematic of the actual mixer is here:
(eeeer, on the potentiometers, pin 3 ISN'T connected and C1/C2/C3 are non-existant)
The amps are TL074CN

Now, in a completely separate circuit I control the Digital Potentiometers which is powered over an arduino nano which in turn is powered over my pc (currently)
Okay, that's the circuit as built when it worked. Now draw the version that doesn't work (everything- don't just pretend the digital pots are drop-in replacements).
Sorry it took so long, I was hit with some unexpected busyness.

The digital potentiometers are literately used as a opt-in, anyhow, here's the schematic:

The VDD is connected to +5V and the VSS to GND, the arduino is powered over my compter (so a different power source than the amps).
1-You need to have common grounds, so that the ground on the Arduino is the same as the ground on you mixer. I don't see any power supplies on this at all, how are you powering this?
2-I took a quick look at the Datasheet, and /SHDN and /RS shouldn't be floating, they need a pullup to Vcc to be active
3- the lack of bypass caps is making me twitch. You need at least a 0.1 uF at the Vcc of each part.
Can you please share the specifications of the all of the components?
Also how it is connected with the Arduino and how it is working with that Arduino?
How i can select the capacitors and pots value based on the frequency required in the circuit?

pcb prototypes
  
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