iPod Serial play/pause

teejaytiger:
Anything visibly wrong here? Did it become a hardware problem?

The soldering doesn't look very good.

Are those arrows data direction flow? In which case you have data on the receive line pointing the wrong way.

I have one of those level shifting boards. You have to power them. The HV and LV pins appear unconnected. The board has transistors on it. Transistors need power to work.