I think there is something wrong with this unit, tested 4 different units and sometimes it gets hot

for no reason if the input audio jack is not connected and it burns! It does not make any sense because

inside theres only 64 resistors with a common pin...... if you know something let me know, otherwise DO NOT USE IT.

Sourcecode here

GERBER here

 

4021-layout

 

4021-scheme

 

VOLUME-MCP4021 00

 

digital pot