i know, i know, i know, sounds nice!

But the initialisation part of the bootloader disturb
the device from clean and smooty functional start.
That is the reason FLIP does not operate always
successful on starting your USB device or bootloader.

I have rewritten part of the bootloader autodetection
USB clock. That part is BAD in the original bootloader.
When rewritten i have detected, while debugging, the
USB device properly starts up and begins his job.

But thank you for your answer!