Problem with phone line?

Another test you could try is plugging in a different phone. Try using a corded phone if your phone is cordless or a cordless phone if yours is corded. Other then that the only thing is for the phone company to run some tests on your line to see if there are any problems, then if one is found get a engineer to check and fix the problem. Usually they can find the problem by running a text down your line from their end.