Usual problem. RNS-510 stopped in German mode, no sound, no radio, phone integrates but no speaker volume. Presume this is caused by either:
a. failed battery and voltage variation with cranking that turned the dash/maxidot on/off repeatedly.
b. hard drive failure.

Thought I may as well try to swap to SSD. Following the DIY instructions (John C and Kamold), fairly straightforward. Trying firmware 5238. But forgot the best method for CD/DVD burning and the disc wouldn't read, got stuck and wouldn't eject. (Been there in 2012 doing custom boot loader - have reread the recipe.)

Had to pull the CD/DVD drive out. Can't find any manual eject facility on the mechanism or figure how to manually lower the disc blocking tabs.
Had to loosen the front the get the disc out. Attempt 2 - the CD/DVD drive still wants to stay locked.

Somehow between unplugging the power and reinstalling the Hitachi original drive, the CD/DVD resets itself and will accept a disc.

Got an error:
SWL CD detected but invalid Clamp State - please removed the (ejected) CD and either:
a. change the clamp state to Hour Mode and re-insert the CD or
b. press any of the Menu buttons to continue with normal operation.
Not knowing anything about clamp state, i did b! Firmware happily updated on the old hard drive.

At this point I didn't really want to install the maps on the old hard drive. Swapped out the old drive for the SSD and tried to reinstall the 5238 firmware. Apparently, the unit might not like this. Unit probably got confused when i poked in the SWL DVD instead of the maps DVD. Same disc that worked last time isn't doing anything this time.

Have to disassemble the CD/DVD to retrieve the disc. But can't get the unit out of locked mode.

VCDS says the eject button is enabled. Apparently there is also some "transport mode", but maybe it's the same as eject button disable. Can't find anything obvious about transport mode. It appears the feature was created because cars were shipped with maps DVD in the CD/DVD drive and lots were getting nicked, so the CD/DVD lock is meant to stop people easily getting the discs out.

At this point, my RNS-510 is partly functional with firmware 5238, empty drive, no maps, no nav, until I can at least install maps on the old hard drive. Maybe it will be happy if I poke the maps dvd in to the disassembled drive and let it do it's thing. Have to burn a duplicate so the original doesn't get ruined.

(Plan C was to duplicate the drive, but my pre-reading didn't get as far as saying newer RNS-510s have 40GB drives. I was happy to get a 32GB since I don't have any music on the drive. So I can't clone the hard drive to SSD unless I get a bigger SSD.)

SSP 397 on RNS says "switch-off time" used to be called "hour mode" or "hour logic", but is now 30 mins. Not sure how that relates to the CD/DVD clamp. I'm guessing that the "clamp" requires some combination of map installation and transport mode being turned off to release the maps DVD to the vehicle owner.

My GTI says:
Note: If you receive a clamp state error ‘a swl disk is detected but it is unvalid because of clamp state. please switch clamp state to hour mode and re insert disk’ this means you need to change the time format of the clock in the RNS 510 from 12 hour to 24 hour clock.
Will have to try that.....

So can someone tell me how to get the CD/DVD out of "locked/clamped" mode????? I presume once I can get a disk in I will be either able to downgrade the firmware via the secret menu downgrade mode or just reinstall the same version over the top to initialise the new SSD.