I tried to put on CD with speed 1x, 2x, 4x, ... and still is the same problem "Please insert upgrade cd". I used Verbatim and maxell CD.
I also tried to change HDD, and the same message.
When I put the CD with firmware on radio, it trying to read for some seconds (the disc is running for few seconds), stopped running, and staying inside for around 20 minutes. When I put the audio CD on radio, immediately getting out.
I tried to use 8.31 and 8.20 firmware.
If someone had this problem, or what should be a problem.