my stock 10"sub makes a very annoying noise and gets louder every time i accelereate LINcoln Navigator some1plz tell me what to do

Check your grounds on the amp...also make sure you have sheilded spark plug cables. But I'm thinking the ground on the Subs amp probably is loose or poorly placed.

Also when checking the grounds make sure to clean them...sometimes a film can build up on electrical contacts and can almost act as a rectifier. Cleaning these contacts might solve the problem.

stock?? Is it a whining, a rumbling or a popping noise?