I have one with rockbox installed and with probably failing flash memory.
It looks like that:
1. I turn it on and rockbox boot screen is there for ~minute.
2. Then it reports in text about failing checksum, bootloader checksum is always the same, main firmware has different checksums every time
3. Then it invites me to insert USB plug and then -- "usb bootloader mode"
In this mode, the player shows itself in `lsusb`, but sometimes `sudo lsusb -v` fails to read all the descriptors (with some error messages in dmesg). Sometimes the player shows a 4Gbytes disk device that contains just a repetition of the same garbage data and eventually reading it with `xxd /dev/sdb` fails with error messages in dmesg.
I suspect failing flash chip, and here are my questions:
1. Is there any way to repair flash contents without desoldering the chip?
2. If desoldering, which chips would work?
3. Is there any firmware image that could be flashed directly in flash chip?