my situation is a little bit different.
moode works also fine incl. hdmi output at pizero.
but volumio starts first with a sdram error (led blinking 8 times) - after a kernel-update on a working rpi B+ it works fine.
runeaudio doesn't start or boot - no activity on led.
in fact:
pi zero works
sdcard works
supply works
rune-img doesnt work - why? i tried all rpi1 images without success
greetz