I noticed in my wedding confirmation letter from my Hotel that there's a clause that says "MACP permit licence fee, PPM license fee and PRISM license fee" is required for event held in the ballroom should there be any performance of music either laptop, mobile machine, dee jay or live performance by artistes.

Does this mean I need to apply and pay for a licence if I were to play my wedding slideshow with background songs during event?

By right, you need. The matter is do they really applied for license and submit the fee.

well..usually the enforcers will close a blind eye on these events as it is "small fish" to them. No point wasting time asking you to pay for like few hundred for a 1 day event. So legally it is payable but you could most probably get away with it unless you have guests who are from MACP....