The before mentioned firmware update is coming up:
However at the moment it is only text at the above page - no files to download.
Just copy the text from this page (head-direct) then open a new browser page, paste the text to new browser page command line or use this link: http://down.head-direct.com/HM-602-v0.04.zip
once press enter it should ask for the target folder to save the zip file.
I have updated my HM602, the firmware seems to handle SD cards better, however I found that the old firmware worked with some music formats such as APE and WMA better than this version, i got unit frozen everytime trying to play these formats with new firmware.