What is the word for something that is dysfunctional because of it being old and in use for a very long time?
I was having a conversation with my friend yesterday about the earphones I use with my computer:
Friend: Your earphones are horrible, one side does not work and voice is also disturbed.
Me: What do you expect? I have been using them for the past two years, this is how long they last.
When I was imagining this conversation about keys, I described keys as rusty, which will imply that they are old. Is there a word along the same line for dysfunctional cars, computers, or something similar?