Muffled Audio with Audio+ V2 [resolved]

I purchased a coupled of Audio+ V2 shields with the intention of getting them set up to as an alternative to Sonos for streaming audio from my plex media server in my house.

The problem I am facing now is that the audio works but sounds like a box is put in front of my speakers with how muffled they sound. The problem exists both with the test sound when first installing the driver for raspberry pi in addition to how I am playing the audio from my plex library, linked below. I have attached the Audio+ V2 up to my AV Receiver and a set of powered bookshelf speakers I have and changing between them appears to have no affect.

I have tried it with both my Raspberry Pi 3B and Pi 3B+ using Debian Bullseye Lite 64 Bit.

If anyone has any suggestions for a solution or has any context for what may be causing it would be greatly appreciated.

Hi !

So are you using our installation script ?
Your audio+ is compatible with the Hifi Berry DAC + described here so you can use any tutorial for plex using this board.

It’s very unlikely that your 2 boards are defective, also try another amp or an headset (volume will be low) to test the quality.

Let me know,

Yes I did use the installation script prior to following the instructions for Plexamp and did configure Plexamp to use the Hifi Berry DAC+ in that installation.

I have tried a plugging some headphones directly into the Audio+ V2 and a headphone amp and the same muffled (tinny) audio persists. I also uploaded a known good wav file to my pi and played it using aplay and it exhibited the same muffled (tinny) sound.

I feel as though it is likely something to do with the software but I can’t seem to find the culprit as I have a nearly clean install and the fact that the problem persists when using plexamp or playing a wav file through aplay.

Any further suggestions would be greatly appreciated.

I have also tried installing Volumio and playing backing audio from there I am still get the muffled (tinny) output.

“tinny”? what do you mean
The Audio + have a line level output, so you need an amplified speaker to plug it to.

The level is not like as loud as an headphone

OK there is indeed a problem on the last batch of Audio V2, the filtering capacitor value is wrong.
So no worry we will fix it, send me your Amazon order number for a full refund.

A quick solution for you to unsolder (or destroy) C14 and C15 on the right and left side of the jack. You can of course keep the cards for free.

The stock will be fixed soon, so nobody could buy this batch, only a couple clients were supplied with this batch.

Thanks for helping us to detect the issue so quickly

Removing those Capacitors did indeed resolve the issue I was seeing.

For the few customers notified by email with this issue those are the 2 capacitors to remove.

The notice via Amazon said I could smash the capacitors. What is the best way to do that? Pliers? Cutters? Other tool?
Sorry, but I’m not fluent in hardware ECs but I would like to learn!

The cleanest way is to use a soldering iron at around 360 C put a bit of soldering to allow a good thermal conduction in the 2 pads of the capacitors and remove them.

If you do not have a soldering use a pair of cutting pliers to destroy them by cutting in the middle. Protect your eyes with glasses to avoid pieces of ceramic jumping in your eyes.

I too purchased a defective board and received the message to remove or “smash” C14 and C15…

Those capacitors are there for a reason. I assume they are filters…

Q: could you provide me w specs for the caps and I will try to replace them?


Sure, in the original correct design C14 C15 are 50V 2.2nF ±5% 0805 package
I personnaly can’t hear the difference when C14 and C15 are not implemented versus when there is 2.2nF. It is here theoricaly here to filter any potential electromagnetic noise frome the power supply, but I never heard some on the Audio+, maybe because I have inclued on the Audio+ a separate power supply for the DAC generated from the RPi 5v.

But feel free to let me know if you hear a difference.


Thanks for the reply! Much appreciated! Thanks also for the refund!

I will try without c14/c15 caps. If I can hear any noise from the power supply, ill install them