I could confirm, that the OnOff Shim doesn’t support a Raspberry Pi 4B with below listed peripherals:
-
analog speakers (Trust Compact 2.0, 6 Watts peak). The Power is drained via USB connection from the Pi. -
Neuftech card reader connected via USB) -
27" Monitor (Dell U2715H) connected via HDMI -
Powerbank (EasyAcc PB26000MS) as power supply
However, connecting the power bank directly via USB-C plug works like a charm. See also OnOff Shim @ Pi 4 - Unter-voltage issues?