I know this is a year old, but I've found the issue and it might be helpful for others with this issue.

If you're using the ESP8266Audio libraries with M5Core2 v0.1.4 or v0.1.5, and you're running "M5.begin()", you need to comment out "Spk.begin();" in "M5Core2.cpp" in your libraries. ie:

// Spk.begin();

And add this to your code:

M5.Axp.SetSpkEnable(true);

I don't really understand why this is causing the issue but I noticed v0.1.3 (which works fine) had the speaker initialisation function commented out.
A year late in my reply, but better late than never!

I know this is a year old, but I've found the issue and it might be helpful for others with this issue.

If you're using the ESP8266Audio libraries with M5Core2 v0.1.4 or v0.1.5, and you're running "M5.begin()", you need to comment out "Spk.begin();" in "M5Core2.cpp" in your libraries. ie:

// Spk.begin();

And add this to your code:

M5.Axp.SetSpkEnable(true);

I don't really understand why this is causing the issue but I noticed v0.1.3 (which works fine) had the speaker initialisation function commented out.
A year late in my reply, but better late than never!

Well, it's working.

The path to my Windows profile has a space in it. I created a local account without a space, and my empty program compiled with no issues. Don't know if that's the reason. Very strange.

Makes me want to reinstall Ubuntu, or something.

Thanks for the replies, Terry.

Yeah, I'm using v2.0.3
I installed the "M5Stack" boards, and then the "M5Core2" libraries, including dependencies. I've tried different versions of the boards.

I'm I missing something obvious?

Hi, thanks for the reply.

While writing my reply, I realised I misread the error. Arduino IDE cannot find "bits/c++allocator.h" which indeed doesn't exist in this directory. It exists in multiple different directories, though.

I coped "c++allocator.h" into the path stated in my original post, and it got over this error. But, it's now missing another file.

I could copy all these missing files (assuming there's more), but something seems to be wrong here.

My code has the following with empty setup and loop:

#include <M5Core2.h>

When I verify, it terminates with this:

c:\users\xxxxx xxxxx\appdata\local\arduino15\packages\m5stack\tools\xtensa-esp32-elf-gcc\gcc8_4_0-esp-2021r2-patch5\xtensa-esp32-elf\include\c++\8.4.0\bits\allocator.h:46:10: fatal error: bits/c++allocator.h: No such file or directory

The file does exist in that location. File doesn't exist in this location, but exists in other directories.

I'm compiling this on a Core 2, using this guide:

https://docs.m5stack.com/en/quick_start/core2/arduino

So, what am I doing wrong?

Hi, I see that the default micropython v1.12 firmware for Core 2 only uses 2Mb of PSRAM.

Can anyone help with how to recompile this to use the full 8MB of PSRAM that is on the Core 2?