Firmware cannot be unlocked (3.0 RC2)

[altglass]

I cannot get to install the lejos 3.0 RC2 firmware to my RCX 2.0.
This is what firmdl tells me:

Code: Select all

read firmware srec
  100%
Installing firmware
Loading native libs
Deleting firmware
Firmware deleted
Downloading firmware
  100%
Firmware downloaded
Unlocking firmware
Unlock firmware failed: Tower error: no response from rcx

At that point my RCX beeps several times in a high pitch and on the display it says 7.8 0.

This does not happen with lejos 2.1.0.

What might cause that problem?

Also is there still active development for lejos on RCX or has it all shifted to NXT?

[bnl]

Bad batteries?
I downloaded the firmware to 2 different rcx brick, with no fuss.
/Björn