Heh, I had one of those players as well. A coworker of mine purchased it, didn't use it often and when he decided to use it for biking, it stopped working. In the meantime the company went out of business and he couldn't even get it serviced. So he gave it to me. I did manage to fix it after waiting for spare parts for many weeks.
The reason why it looks like a Toblerone bar is because they decided to use through-hole electrolytic capacitors (because audiophile reasons) and the battery was round too (an 18650 IIRC): http://mikebeauchamp.com/wp-content/gallery/pono-teardown/ca...
The triangular shape and inability to carry it comfortably in jeans pants pockets doomed it from day one. I'm amazed something like this passed the design stage. And first encounter with user testing would have made it crystal clear that the shape was a no-go. Yet it not only got funded but was also mass-produced. It was a massive waste of money.
I mean, it plays, and the audio quality was good (doubtful it was due to the reasons they claim, but it was good). But I hated the screen and you're right, the form factor would have never passed a focus group that tried to actually use it.
http://tenfourfox.blogspot.com/2015/01/and-now-for-something...