McCORMACK DNA-1

My beloved McCormack DNA-1 red Protect light no longer fades out at startup.   It has worked well with my McIntosh MX-110 preamp for years!  Is it a possible fuse, or do I need to send it in for service?

Also the last I remember, Steve McCormack was in San Diego, CA and offered upgrades to these units.  Is this still available?

Appreciate any feedback,

skidude48