Noise on speakers output and power supply for web radio

[z34pec]

Number One:
I suppose many of you have noticed that there is a noise on speakers like humming or similar. It is because of using same power supply for amplifier and for esp32.
You can solve this problem with these two things:

1. Put audio transformer 600:600 to each input line, before sound signal enter to amplifier.
2. Use electrolitic capacitor 47, 33 or 22 uF / 16V or higher voltage between 8 pin on pam8403 amplifier IC and GND at the input of signal on pam8403 amplifier board. Positive leg of capacitor goes to GND and negative goes to pin8 on PAM8403 IC

I use both solutions for eliminating noise on my speakers.

Number Two:
Using 5V/2A power supply from phone chargers is not enough for suplying esp32, pam8403 and VS1053 MP3 module . You will face random restarts. It is good to use LM2596 Step Down Module, and use 12V/2A power supply, because step convertor can supply up to 3A. This combination can give enough power for full power of PAM8403 :)