Kill it. It annoys me.

Don't sit around in the station and it won't be a problem. :P

Kill Death Fluffy, he annoys me.

Kill Death Fluffy, he is annoying yoda, who annoys me.

/explode

Moved to suggestions.

I'm not really sure why this was moved to suggestions since I cannot imagine why you would hear the hum of a holographic external sign inside a station. Sure, it's kind of cute when you fly through them.

It's somewhat annoying if you spend any amount of time working out of that station and should be fixed.

"I cannot imagine why you would hear the hum "

Well, that would be because you can hear other stuff that happens outside the station as well, which IMO is a Good Thing, as it helps you know when convoys have undocked or dudes are fighting and stuff, and is a nice effect.

I haven't been in O15 for a while but don't remember any signs ever bugging me. Maybe you should turn your volume down.