My CRAFTsynth 2.0 turns on and looks like it's working, but there is no / low sound.
Check that all of the connectors are attached properly.
Check that your headphones or line connection are connected properly and working as they should (testing with another device that provides sound is an excellent way to do this).
Try sending MIDI to the CRAFTsynth 2.0 to identify if it is an issue with the touchpads.
If connected to a device with a balanced input (e.g. an audio interface), you will need to use a TS/mono audio cable rather than a TRS / stereo cable. Both channels of the CRAFTsynth 2.0 output are the same, meaning that using a TRS cable into a balanced input will result in the two signals partially cancelling each other out and therefore causing a lower audio output.
Check the patch parameters and global settings. Three parameters can affect the volume of CRAFTsynth 2.0.
The VOLUME control sets the final master volume at the output stage.
The AEG-DEPTH sets the maximum level that the AEG can reach before returning to 0, and as this parameter is saved per-patch, it can be used to level balance between patches, or modulated to produce AM effects.
The AEG Sustain level determines what level the DECAY phase will reduce down to. Both ATTACK and DECAY default to 0 on an init patch, so your SUSTAIN level will determine how loud your sustained notes are in this situation.