I already added the Bluetooth module several weeks ago. Unfortunately the module was not working. Only the left channel played music and there were a lot of interferences. Since I had already used the same module it was clear that the device is broken.
Delivery times are horrible at the moment – as for all who are waiting for ICs – it took almost two months got get a replacement. But now everything is working fine with clear sound and no interferences. Compared to the first implementation were the module got power all the time, not only when it’s on AUX I now searched for a different solution. It is not comfortable to close the connection all the time.
A DC/DC converter separates the ground signal and reduces interferences in the audio channel. To place the module on top I created a small bracket. I decided to connect the cables right at the AUX input so I can keep the 10k input resistors. Well, might not look as “professional” as it should…
I noticed an open contact at the MONO/STEREO switch which I used to power the module on/off. The module has internal relays and it is easy to switch between AUX and Bluetooth by just switching the module on or off.
Now I need to continue with uploading videos and describing the steps to implement the Bluetooth module.
