Getting unexpected MP3 sync words Options

[RonBowater]

Hi ... I'm writing a player in Java for Internet radio stations using the Javazoom library to do the MP3 decode. It's all working pretty well apart from a 'hiccup' in the audio every 5 seconds or so. I've traced this down to where the decoder gets MP3 frames with a non-standard syncword i.e. usually it is 0xFFFFF330 but every 5 seconds I see a frame with the top byte set to something different e.g. sync word 0x9EFFF330, 0xCDFFF330 etc. I searched high and low on Google to see whether sync words other than 11 leading 1's mean anything specific but I can't find anything relevant.

Can anyone offer an explanation for these strange sync words please ?

Thanks
Ron