将缓冲区从PSRAM通过SD_MMC获得的文件描述符f.write()写入SD卡的速度相当缓慢，只有0.5MB每秒
最快的方法应该是通过DMA直接从PSRAM搬运数据到SD卡，但是我没有找到相关的例程
有人知道我应该怎么做吗？

已经查看https://esp32.com/viewtopic.php?t=13758, 不过那是对于esp32而言
我现在使用的是ESP32S3， 4bit SDIO

ESP32S3没有硬件fft加速器，计算起来太慢了。执行1024浮点运算需要300~600us。
有人知道什么硬件可以通过UART或者其他协议挂载并协助FFT计算吗？

最好查看pinout或者数据表谨慎选择使用的引脚，有些引脚不是GPIO，用了就会产生问题

I don't think you can minimize sketch if those library does not provide custom option.

In platformIO, you can do:

[env:esp32dev]
platform = espressif32
board = esp32dev
framework = arduino
board_build.partitions = huge_app.csv

I have not try this in ArduinoIDE but I will assume solution is similar.

Assuming your PCB is ok, and assuming their library is ok, then the problem may be with your code. Is your wav file single channel, if not you can't write it to i2s directly like the example code you show does.

Hard to tell where exactly the problem is. But speaking with the parameter, It's not clear exactly which i2s format micropython calls the underlying i2s controller. Maybe check the format configuration (Pin16 of PCM5102A) in your PCB first.

You can assess datasheet to view the circuit diagram and understand how to start to use their module: https://www.espressif.com/sites/default/files/documentation/esp32-wroom-32e_esp32-wroom-32ue_datasheet_en.pdf
Often they provide simple power supply instructions and a startup reset circuit design ...

void setup() {
Serial.begin(115200);
delay(1000);

fft_in = (float*)heap_caps_malloc(2 * N * sizeof(float), MALLOC_CAP_SPIRAM);

if (fft_in != nullptr) Serial.println("✅ PSRAM 分配成功！");
dsps_fft2r_init_fc32(NULL, CONFIG_DSP_MAX_FFT_SIZE);
// 生成测试信号
for (int i = 0; i < N; i++) {
float t ...