The ADDAC501 does random CV generation and outputs it through three independent channels. You can control the desired range of voltages and time frequency at which new values are generated.
It can also be triggered by an external CV source and the output voltages can be either free or quantized (if you prefer to have a standard C Major Pentatonic scale).
Finally you can choose between pure randomness or a brownian distribution, for both the voltage and time intervals.
Specs:
120 mA 12V
20 mA -12V
0 mA 5V
8hp