Playback stops (but not fully) when changing volume too quickly

- Arduino board: **Adafruit Feather RP2040 rev D board**
- Arduino IDE version (found in Arduino -> About Arduino menu): **2.2.1
Date: 2023-08-31T13:53:43.373Z**

I'm using a Rev D Music Maker FeatherWing. I noticed this issue when adjusting the volume via a potentiometer, but I was able to reproduce it with just the Feather and FeatherWing by varying the volume as a function of elapsed time. With 1-2 ms of `delay` inside of `loop()`, the playback reliably stops somewhat randomly. With higher values of `delay`, the pausing is less frequent but still reproducible.

An odd detail is that `playingMusic` still returns `true`, and if I trigger a pause and then play with `pausePlaying(true)` and `pausePlaying(false)`, the music picks up where it left off.

Per `musicPlayer.sciRead(VS1053_REG_VOLUME)`, the volume levels are being set correctly on the MusicMaker.

[[Adafruit Forum Thread](https://forums.adafruit.com/viewtopic.php?p=994328)]

Full sample code:

```ino
#include
#include

// Correct pins via
// https://flashgamer.com/blog/comments/using-feather-rp2040-with-adafruits-music-maker-featherwing

// These are the pins used
#define VS1053_RESET -1 // VS1053 reset pin (not used!)

// Feather RP2040 - MusicMaker FeatherWing
#define VS1053_CS 8 // VS1053 chip select pin (output)
#define VS1053_DCS 10 // VS1053 Data/command select pin (output)
#define CARDCS 7 // Card chip select pin
#define VS1053_DREQ 9 // VS1053 Data request, ideally an Interrupt pin

Adafruit_VS1053_FilePlayer musicPlayer =
Adafruit_VS1053_FilePlayer(VS1053_RESET, VS1053_CS, VS1053_DCS, VS1053_DREQ, CARDCS);

void setup() {
Serial.begin(115200);
while (!Serial) {
delay(1);
}

if (musicPlayer.begin()) { // initialise the music player
Serial.println(F("VS1053 found"));
} else {
Serial.print(F("Couldn't find VS1053. Do you have the right pins defined?"));
}

if (!SD.begin(CARDCS)) {
Serial.println(F("SD failed, or not present"));
while (1)
; // don't do anything more
}
Serial.println(F("SD OK!"));

SD.open("/Music");

// If DREQ is on an interrupt pin we can do background
// audio playing. In this case, #if defined(__AVR_ATmega32U4__) will be false.
if (musicPlayer.useInterrupt(VS1053_FILEPLAYER_PIN_INT)) { // DREQ int
Serial.println(F("Able to use interrupt"));
} else {
Serial.println(F("Can't use interrupt"));
}

musicPlayer.setVolume(30, 30);

musicPlayer.startPlayingFile("0012 Hush_Little_Baby.mp3"); // replace with a file you have on the SD card in the /Music folder
delay(3000);
Serial.println(F("Starting loop"));
}

void loop() {
auto seconds = (float)millis() / 1000.0;
auto normalizedVolume = sin(seconds * 10);
auto volume = floatMap(normalizedVolume, -1, 1, 45, 5); // larger numbers are quieter
// Serial.println(volume); // uncomment if you want to see what we're setting the volume to
musicPlayer.setVolume(volume, volume);
auto readVolume = musicPlayer.sciRead(VS1053_REG_VOLUME);
Serial.print(F("Set: "));
Serial.print(volume);
Serial.print(F(", get: "));
Serial.print(readVolume >> 8);
Serial.print(F(", "));
Serial.println(readVolume & 0xFF);
delay(1); // 1 or 2 reproduces reliably, anything higher reproduces more sporadically
}

/// Float version of https://www.arduino.cc/reference/en/language/functions/math/map/
float floatMap(float x, float in_min, float in_max, float out_min, float out_max) {
return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min;
}
```

Audio used (place in /Music folder on SD card):

[0012 Hush_Little_Baby.mp3.zip](https://github.com/adafruit/Adafruit_VS1053_Library/files/13462609/0012.Hush_Little_Baby.mp3.zip)

Start by reproducing the provided full sample code on the Adafruit Feather RP2040 rev D with the Rev D Music Maker FeatherWing, using the 1–2 ms loop delay. Then inspect the library entry points used here, especially setVolume, sciRead, playingMusic, and pausePlaying. Done means rapid volume updates no longer interrupt playback while the reported volume remains correct.

Written by the indexing model from the issue text.