I get stuttering from ANR even from disk based streams when I do something else, like loading something. Fix it!
ANR needs CPU power to play mp3 and to stream. Some stuttering is unavoidable on weaker CPUs in multitasking situations. Try reducing scope effects or mpeg quality to get some CPU time back. Also, running Petri Nordlund's excellent Executive can "steal" CPU time away from ANR. If you really don't like the stuttering, try setting the priority of the AmiNetRadio task above the dynamic priority range, or set to Leave Alone. If you don't run Executive, you can also use the cli argument (or tooltype) DECODERPRI=1. See "Shell arguments" in the guide for more info.