This PreSonus DigiMax LT 8-Channel Microphone Preamp comes with a correct power supply, which is essential for its proper operation. However, there are a few known issues. The gain knob on channel 8 is shaved off, and the gain knobs on channels 6 and 7 are missing.

To use this PreSonus DigiMax LT 8 - Channel Microphone Preamp, first make sure to connect the correct power supply. Once it's powered on, you can start using it to amplify your microphone signals. But be aware that due to the missing gain knobs on channels 6 and 7 and the shaved - off gain knob on channel 8, you may need to use alternative methods to adjust the gain on these channels. For maintenance, keep the preamp in a dry and clean place. Avoid exposing it to extreme temperatures or humidity. When not in use, unplug the power supply to prevent any potential electrical issues.