stops

i have a sony mhc rg333.When i put a cassette,i press play and after 3 or 4 minutes it stops and i have to press play again(the play button is electric, no the original buttons)

I open my laptop (while its on) and touch anything metal with my skin and it stops. It doesn't stop when I apply pressure using my fingernail. Laptop must be on to hear the noise. Static sound isn't affected by volume meter or audio being played. Static sound is audible when audio is being...