Sound Project DC power supply question

[BMK]

I am working on a sound application project for my model railroad and have questions regarding the DC power supply requirements.
Based on the documentations, when 5VDC input is required, I need to utilize two (2) 1N4001 diodes in series to one of the two DC input pins. Not sure why put OK that is what I will do. However, if I have the unit connected to my 5VDC supply and the USB plugged in at the same time is their any conflicts?

The sound module is a WT588D-U

Thank you for your response
Brian Krupicka USA

[pebe]

Without sight of the documentation and your circuit/ wiring arrangement, it is not possible to give an answer.