MetroCard mystery

So I have long despised my iPod earbuds. Lately, they've been giving me tiny electric shocks, especially when I'm walking outside with my coat on (as a result I have shelved them indefinitely and am saving up for a nice pair of over-the-ear noise-cancelling ones).

Yes, whenever movement caused any tugging on the earbuds, they would crackle and occasionally I would feel a kind of electric pulse, though nothing I thought was serious. The other day - the last day I used them - I got a very noticeable electric shock after using them on the walk to the office and then touching my computer to turn it on. Again, nothing real serious, but certainly remarkable. Anyway the day wore on, and I eventually forgot about it.

However, when I went to take the PATH train that evening, my MetroCard kept getting spit back up by the machine. I took it over to the subway, where they have the swipe to check your balance. "See Agent" it told me. So I brought it to the booth attendant and he tested it. "That's strange," he said. "It has a balance on it, but it won't read properly."

He gave me a form and an envelope and told me to mail it to the MTA and ask for a refund if it still wasn't working the next day. It wasn't and I sent in the form.

The MetroCard was in my coat pocket, which I was wearing when I got the shock from the computer. Now, I passed science by humming Monty Python tunes and guessing randomly, so maybe I'm way off base here. But could there be a connection?