Button “ RELEASE FX “ Blue light not lit

Hello Dear Friends,

The “ Pioneer DDJ 400 “ controls I had 3 months ago Button “ RELEASE FX “ Blue light not lit. There is no problem with the button functionality. Only the blue light is not on, that is, it does not give ON/OFF status information.

1. Is this Firmware or software problem? Can we solve this Problem ourselves?
2. Does it need to be physically rebuilt? What are the chances of it being faulty?

I do not want the device to be involved in the service process for the repair of the blue LED light.
Hopefully it's a software related issue and someone can assist with a solution.

Thanks.
Respects