Not sure if the OS update of 1.11B to 1.12 was in the last few months, but there was a CV update.
From the OS1.12E read me:
List of changes from OS 1.11B to 1.12
Changes
CV Pitch Config
The way pitch CV output is configured has been changed to be easier and more precise.
This manifests in new options in the CV CONFIG menu for the TYPE settings PITCH V/OCT and PITCH HZ/V.
CV pitch is now configured by finding the voltages generating two different notes from the synthesizer you wish to control. To get a good result you should select the notes two or three octaves apart
Before configuring the pitch output you should setup a gate output so that notes can be triggered on the receiving end. You should also set up the gate and pitch parameters so that they use the same source track for triggering notes.
Then select NOTE 1, it could for example be C-3. Then highlight VOLTAGE 1 and press [YES/SAVE]. This will trigger a C 3 note which is played for as long as you hold down the key. While keeping [YES/SAVE] pressed, adjust the voltage until the controlled synthesizer actually plays the note C 3 using [LEFT]/[RIGHT] keys or the A encoder. If you don’t have a tuning device, the easiest way is to play the corresponding note on one of the Analog Four’s internal tracks and tune by ear.
Repeat the process for NOTE 2 and VOLTAGE 2, but choose for instance C 5 or C 6.
Finally play some random notes to see if they are in tune. If not, then you probably need to change from V/OCT to HZ/V or vice versa. That’s all.
CV Trim Settings
CV VOLTAGE TRIM is a new menu which can be reached from CV CONFIG in GLOBAL.
From this menu it is possible to trim the CV out voltage levels. These settings are stored in the machine without being connected to a project.
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Make sure you have a good voltmeter before proceeding. Connect a TRS cable to the output you want to trim. Connect the volt meter’s negative terminal to the sleeve of the connector. Connect the positive terminal to either the tip or the ring of the connector, depending on the channel you wish to trim.
Each CV output has three trim settings. Begin by selecting 0 V, then press and hold [YES/SAVE]. 0 V is output as long as [YES/SAVE] is held down. Use [LEFT]/[RIGHT] keys or the A encoder to adjust the voltage until your voltmeter shows exactly 0 V. Repeat the process for both 8 V settings (one is for continuous voltage, the other for pulse).
Note that adjusting the CV does not actually improve CV pitch control. If you have set up pitch control of an external synth properly then any linear error has already been compensated for by that calibration. In fact, you will have to reconfigure the CV pitch control after changing the values in the CV Trim Menu, because you’ve changed the point of reference.
Adjusting the values in this menu is mainly beneficial if you wish to send pulses with very exact voltage levels, or to generate very specific voltages as a linear value and you believe that the factory trim is off.