Help with modifying a record-able birthday card?

i have a record-able birthday card for a project i'm working on. it uses the speaker as the mic so its easy enough to wire that to a headphone jack and record sound from the computer, but my problem is that i didn't check the card before i bought it and after it plays the noise you have recorded it plays a prerecorded song. how do i modify it so i can remove or change the prerecorded song that plays after my own recording?

I'm no expert (at all) on those things, but I believe the song is preprogrammed into the microprocessing chip or memory chip of the card. Without a programmer and a big headache, I don't think you'll be able to cut off the song nor change it.

Recommend a blank "recording card" that has no song, and buy that one :)