HP50g buggy / strange key behavior

[tryxan]

Hi,
I got myself a used hp50g -in mint condition- after my beloved 49 stopped powering on lately
I noticed a strange behavior of the 0 key, it freezes everything until released :
If I press and hold 1 I get a 1 with the blinking arrow but if I press and hold 0 I get nothing before I release the key. Even the clock : stop blinking.
This also happen with ON, APPS and VAR keys that all only activate on release.
All work OK in the ON-D keyboard test so I would say hardware is OK.
Can a bad sysRPL program change how keys are handled? even in non USR mode? Or is this a known bug?
There seem to be issues with the emulation layer from what I red on various threads...

[Gil]

0-number-key normal with EMU48 (and the clock continues blinking).

[Craig Bladow]

What version ROM is running on your 50G? The VERSION command will display this information. Pressing the 0 key on my 50G (version 2.15) is no different than pressing the 1 key and the digital clock separator continues to flash while either key is pressed. The ON key does stop the clock separator from flashing, VAR key does not. The APPS key pulls up a menu which hides the clock.

Oh, and welcome to the forum!

[tryxan]

So I did a few ROM swaps to investigate and the bug is present from 2.0, which is consistent with the description: "a completely rewritten keyboard handler to reduce the number of missed keystrokes" Someone must have messed something up there!
The good news is all my keys work ok with 1.23, the bad news is the screen is hum... not managed very well...
Really a bummer cause the speed is great on the 50 otherwise.