How to disable si4703

Hello. So I am working on building a radio/mp3 player. This is my most complicated project so far so I am taking it slow. So basically it will have 2 modes - radio mode(thanks to si4703) and mp3 player mode(thanks to dfplayer mini). The modes can be changed with the pushbuttons. But the thing is, if I am changing the modes, I need to disable one another. Lets say I am listening to radio and want to listen to mp3 songs on dfplayer mini, when I change the mode I have to disable the radio right, and other way around. Dfplayer mini has the sleep() and wakeUp() function, but si4703 doesnt. How can I disable si4703 then? Maybe using bool or something similar. I have tried but failed. The only library that has the disable() function is the library written in Rust.

My library for si4703:
https://github.com/sparkfun/SparkFun_Si4703_Arduino_Library/blob/master/keywords.txt

Rust libary that has disable():
https://docs.rs/si4703/0.1.0/si4703/struct.Si4703.html#method.enable

Test code for si4703:

#include <SparkFunSi4703.h>

#include <SparkFunSi4703.h>
#include <Wire.h>

int resetPin = 2;
int SDIO = A4;
int SCLK = A5;
int STC = 3;

Si4703_Breakout radio(resetPin, SDIO, SCLK, STC);
int channel;
int volume;
char rdsBuffer[10];

void setup()
{
  Serial.begin(9600);
  Serial.println("\n\nSi4703_Breakout Test Sketch");
  Serial.println("===========================");  
  Serial.println("a b     Favourite stations");
  Serial.println("+ -     Volume (max 15)");
  Serial.println("u d     Seek up / down");
  Serial.println("r       Listen for RDS Data (15 sec timeout)");
  Serial.println("Send me a command letter.");
  

  radio.powerOn(); // How do I turn it OFF?
  radio.setVolume(0);
}

void loop()
{
  if (Serial.available())
  {
    char ch = Serial.read();
    if (ch == 'u') 
    {
      channel = radio.seekUp();
      displayInfo();
    } 
    else if (ch == 'd') 
    {
      channel = radio.seekDown();
      displayInfo();
    } 
    else if (ch == '+') 
    {
      volume ++;
      if (volume == 16) volume = 15;
      radio.setVolume(volume);
      displayInfo();
    } 
    else if (ch == '-') 
    {
      volume --;
      if (volume < 0) volume = 0;
      radio.setVolume(volume);
      displayInfo();
    } 
    else if (ch == 'a')
    {
      channel = 930; // Rock FM
      radio.setChannel(channel);
      displayInfo();
    }
    else if (ch == 'b')
    {
      channel = 1075; // BBC R4
      radio.setChannel(channel);
      displayInfo();
    }
    else if (ch == 'r')
    {
      Serial.println("RDS listening");
      radio.readRDS(rdsBuffer, 15000);
      Serial.print("RDS heard:");
      Serial.println(rdsBuffer);      
    }
  }
}

void displayInfo()
{
   Serial.print("Channel:"); Serial.print(channel); 
   Serial.print(" Volume:"); Serial.println(volume); 
}

I don’t know if this even belongs into “Programming questions” but anyway, I hope you understand what I am asking and I hope you can help me.

Best regards,
Me

Can't you just use radio.volume(0)?

The guy here talks about a 16bit configuration register accessible by i2c where can power states, mute and mono/stereo be configured. It might be worth looking through the datasheet for the module and accessing the relevant bits of the register directly from the code.