Sample plays weird, how to make a sound pack?

Hi,
I have a RYTM mkii which has been sitting unused for a couple of years. I am trying to get some use out of it. I loaded a few samples into it via Transfer. a couple of rims, a shaker and a couple of BD. When I preview the bass drums on the RYTM, it just makes kind of a mellow beeping sound. The other samples sound pretty much as they do when I preview them on my Mac.

What might I be doing wrong here?

Also how can I make my own sound packs? loading sound packs and managing files is hell on this thing and the main reason I dont like to spend time on it. Hours perusing manual, googling, instead of making music.

My friends love it and use it in their live sets but I have never gotten past the pain points.

Thanks