I have had an Audible Otis for several years.
It worked pretty well for 2 years or so, then started having problems. Sometimes, it wouldn't load, sometimes it would "hang-up" while playing.
Audible support sent me a new firmware file, and an OS firmware loader.
After upgrading the firmware, it worked OK for a few months, then problems came back.
I have since upgraded my computer, and lost the files from Audible.
Now, it seems to "forget" it's operating system and loaded audio files occasionally, making it necessary to re-install the OS firmware.
After much research, I found that the OTIS is manufactured by HYUN WON. Their support is at either "HyunWon.com" or "M-Any.com".
The OTIS is very similar to the DAH-410/420. The downloadable Loader supplied for the DAH-410/420 includes a browser that will let you move WMA (and other) files into/out of the player and the MMC card.
It will also let you upgrade the OS, but you need to find the correct OTIS OS, save it to your hard drive, then install it to the OTIS from your LOCAL directory. If you attempt the ONLINE upgrade, it will install the DAH-420 firmware in yout OTIS. You will lose some of the functionality of your player, though it will still play Audible and WMA files.
I did this, and was able to recover by re-installing the old OTIS firmware.
You should be able to copy the OTIS OS firmware from a working OTIS player via the AnyLoader program from Hyun Won, then install it into your OTIS player.
There's a risk of really messing up your OTIS player by doing this - be warned.
My Audible Otis MP3 Player 64 MB worked fine for over a year and was great with the audiobooks and decent with my music files, not the greatest sound, but good for travel, very small and portable. Anyway worked great until I update my firmware to the newest version, now my pc doesn't reconise the player when it's plugged in and won't let me add or delete from the Otis player's internal memory .
I deinstalled the upgraded firmware but when I tried to reinstalled the old software that came with the player it automatically updated to the newest version and won't let you finish the installation unless you are online which cause the automatic update. When I called Audible.com they claimed that my old players(I also had an Toshiba e310 on my account that shouldn't work but does since they don't support that model)should work with the upgrade, well the Toshiba does the audible player won't. I was wondering if this has happened to anyone else and if they found any solution to the problem.

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