David, First of all you need to get a hold of the upgrade patch file which is version V1.10C. Then from your computer you'll need to upload this upgrade patch to your es9000 via your PC's serial port and your es9000's RS-232 port. If you don't know what's your amp's version, do the following: 1)Press AUTO FORMAT button.
2)Turn +/- knob counterclockwise.
3)The display will be scrolled.
4)If "TA-E9000ES Vn.nn*" appeared as the last item, the Vn.nn* is the version number.
If "(scroll end)" appeared as the last item, the version is Ver1.01A.

If you want to know more about this, you can go to hometheaterforum.com and search for es9000. Furthermore, there's already a thread entitled "EP9ES & 9000ES" under "Sony RM-AV2000 Chat Forum".