I have a LCS1000 here, and it works well enough for vintage purposes, but wanted to know if someone can confirm it's volume function. The unit has two inputs on the back, and they both work, however only one of the inputs can be adjusted with the volume control on the front. The other input works, but the volume knob has no affect. Just wondering if this was the way it was suppose to work, or if I needed to start looking under the hood for an issue.