My creality silent board has R150 sense resistors not R100 so the VREF formula

TMC2208 - Legacy/standalone mode (as found in Creality silent boards)
VREF = (RMS current * 2.5) / 1.77

is wrong, for details here:

https://www.eevblog.com/forum/chat/3d-printer-yet/msg3271034/#msg3271034