Why is my garage band leaving a delay between playing and recording?

Hello all,

Im a longtime reader - newborn poster to the forums so please bare with me.

Im currently becoming frustrated beyond belief with my new mac mini purchase.

I recently went to the local apple store to discuss my needs and as a bedroom songwriter looking to put 5 or 6 tracks together garageband was a good choice of product. I was told it would work fine on a mac mini to save money as I couldn't afford an iMac at the time.

Ive since found that I have no hope of using the mac as a monitor at all - which ironically i used to be able to do fine on my 5 year old macbook.

More concerning though is that the delay I was once experiencing in the monitor seems to be now effecting my recording time. Iplay notes over the backing track I've recorded but they sound totally out of time (I'm not a great musician, but i can handle playing in time!)

Ive looked up online but most everything i've found is about delays in the monitor, which this is not (yes i get monitor delay, but I've chalked that up to being missed the product in the first place) Is there a way to fix the recording or will I have to take it up with apple? I'm really gutted as I've just gotten this gear and its cost me a small fortune. really hope someone can help.

Thanks all.