Ordered a powerful 48V supply and stepper driver boards to replace the electronics on my small 3040 CNC.
Hopefully that will take care of the lost steps. 
I like that machine. It’s near silent and very portable.
Will keep the mechanics and the silent spindle.
About $80 for the 3x 50V3A stepper drivers and $70 for the 48V12.5A power supply.
(I wanted enough headroom when moving/blocking all 4 axis at high speed/high load. Could have gone with $30 for 8.3A)
I already have a USB board (200KHz on board clock, galvanic isolation for 5V, command buffer, …) that will be left over when I convert my large CNC to Ethernet using a Russian 6 axis board.