I've been trying to control a MP3 player wirelessly through RF but it seems that once I start to play music the receiver stops carrying data to the MCU.
My setup is the following:
Receiver: Arduino Nano, DFPlayer and XY-MK-5V (generic 433MHz receiver). Transmitter: Arduino Nano and FS1000A (generic 433Mhz transmitter).
I'm using the RadioHead library (ASK driver/examples) and the data transmission works perfectly when the mp3 player is on idle mode. When I play the module by short circuiting the play/next pin to ground (or via serial mode) the player operates normally (music starts) but the data transfer from the RF receiver stops immediately.
At first I thought it was a power sharing problem, but I'm powering it through a power bank that allows up to 2A and that is proving power to this circuit at 5.20V / 0.02A. The player's data-sheet (https://github.com/DFRobot/DFRobotDFPlayerMini/blob/master/doc/FN-M16P%2BEmbedded%2BMP3%2BAudio%2BModule%2BDatasheet.pdf) confirms it draws very low current (DC3.3~5.0V, rated current: <15mA) and I couldn't find a data-sheet for the receiver but there is a website pointing its operating voltage at 5V/4mA, so both are very low powered modules.
I realised then it should be an interference with the audio frequency. The player has a built-in 3W amplifier so probably frequencies are going through the power lines and mixing up with the RF.
If I power the audio player with a different power supply it works, but is there another way of avoiding this interference using the same power supply? Or maybe, would another type of RF module work?
Below is my schematics for the receiver circuit. Thank you.