Buzzing noise on WAV file playback from SD card

I have trying to resolve a playback issue when trying to play a .WAV file from an SD card. I'm getting a long buzzing noise, that doesn't sound like my audio clip at all. My .WAV file ("3.WAV") has a recording of a bell ringing. The file plays fine on my laptop in VLC, and sounds as it should. When I play the 3.WAV file on my arduino project I get a long buzzing noise that seems to last for the duration of the actual recording (about 14 seconds), but doesn't sound like original recording at all. The best way I can describe it is it sounds like a pair of buzzing hair clippers.

I'm currently testing my system using this tutorial https://maker.pro/arduino/projects/arduino-audio-player.

I have formatted the .WAV file to 8-bit 16kHz, mono, and set the pcm format to unsigned 8-bit. I've saved the file to an SD card that was freshly formatted, using a simple filename ("3.WAV").

Similar to the tutorial above, I'm using an arduino UNO, along with one of these card readers Amazon.com. I've set up the card reader per the standard pin settings, like what is shown in the tutorial above, namely:
MOSI — pin 11
MISO — pin 12
CLK — pin 13
CS — pin 4

I am not using the amplifier circuit in the tutorial, but using one of these modules: Amazon.com. I have the amp module set up to receive speaker audio from pin 9, and have an 8ohm piezo speaker on the other end of the amp module.

I am testing on the simple sketch gently modified from the tutorial, using my .WAV file (named "3.WAV"):

#include "SD.h"
#define SD_ChipSelectPin 4
#include "TMRpcm.h"
#include "SPI.h"

TMRpcm tmrpcm;

void setup(){
tmrpcm.speakerPin = 9;
Serial.begin(9600);
if (!SD.begin(SD_ChipSelectPin)) {
Serial.println("SD fail");
}
else{
Serial.println("SD OK");
}

tmrpcm.setVolume(1);
tmrpcm.play("3.WAV");
}

void loop(){ }

I've also tested my amplifier using tone(9, 1000, 200) and it sounds great. I feel like the amplifier is working correctly. I've also ran some code to print off the file names of the card to serial, and even printed part of the contents of the .WAV file to serial, so I feel card reader is working correctly as well.

I also tried changing the pcmconfig settings per many of the recommendations online (increased buffer size, etc), tried adjusting the audio.setVolume() parameters, and tried resaving the file at different sample rates, all to no avail.

Can anyone help me figure out the problem? I'm about 8 hours into it now, and still stuck. Much advanced appreciation for any advice!