I purchased this used previously, but I no longer need it, so I'm selling it. Operation confirmed. There is some crackling in the first knob, but I used a PC, so it didn't affect usage. Regarding the condition of the product, it is in good condition for a used item, so I have set the price accordingly. As this is precision equipment, I will pack it carefully, but please refrain from purchasing if you are overly concerned about minor details.