At the start of each tune x11amp prints "decode loop" to stdout (stderr?). Start it from the command line to see. This looks like debug print info which someone forgot to remove. # rpm -qvf `which x11amp` x11amp-0.9_alpha3-6
oops, a debugging printf slipped through. Fixed in x11amp-0.9_beta1.1-2, available in the next Raw Hide release.