(What to do When You Know BETTER.)
Being an intern can be tough. If this comes as news to you, you probably haven't started your internship yet. You're stuck with grunt work, thrown into roles and responsibilities that you feel desperately unprepared for, and you're doing it all for free – or as close to it as local slave-labor laws will allow.
Sometimes, you're even told to do things that you know are wrong. I'm not talking about Agent Orange wrong, or dead-hookers-in-your-trunk wrong, but just things that are . . . technically incorrect. Like applying phantom power to a DI box that doesn't need it, or using the “wrong” mic for a given situation. These kind of things may seem trivial, but it's grating when your mentor tells you to change an EQ curve from one that you like to one that you don't.
What do you do in these situations? Usually, you grin and bear it. If you feel there's a danger of equipment damage (never put 48 volts to a ribbon mic, boys and girls!), then politely voice a question once, and then drop it – if the system blows up, it's not your responsibility.
Look at it this way: Being an intern is sort of like having diplomatic immunity. It's your chance to make just about any mistake without consequences – after all, how could you have known? You're just the dumb intern. (Downside: You don't get special license plates.)
And besides, most of the really valuable lessons you learn from an internship are not what to do, but rather what not to do. So use that “wrong” mic or “bad” EQ curve – take what you can from it, and move on.