What could cause system switch to shut off during runtime?

[funkyfourier]

I have a Raspberry Pi 4 and PiJuice Zero with an amplifier like this hooked up to the system switch which runs in 2100mA mode. There are two 4ohm 3W speakers connected to the amplifier.

During operation the system switch shuts down at seemingly random times (to "Off" position in pijuice_cli). If I go to pijuice_cli and set it back to 2100 it continues to function as expected.

There are other peripherals connected and powered by the RPi: A USB microphone (Samson Go), a HiFiBerry Zero and a touch screen.

Could it be that the amplifier combined with the USB powered peripherals draws too much power so the system switch shuts itself off? Are there any safety measures in place to trigger that behaviour? Or could this be some sort of software bug?

The cables for the amplifier are well connected and as thick as I could fit into the holes on the PiJuice PCB.

Thanks for any ideas or things I could try.

[funkyfourier]

After further testing I am quite certain that it has something to do with limitations in the battery. The shut off does not occur while charging, and it does also not occur when the speakers are disconnected. Would be nice if someone could confirm that the PiJuice has a shut off mechanism on the system switch when the battery gets overloaded.

Is there a chance that a bigger battery, say the 12000mAh one (as opposed to the 5000mAh which I currently use) would tackle the load better?