Built-in 4MD Changer! [Defective Item] Although the main unit's volume dial sometimes decreases or goes to zero even when turned up, the volume can be adjusted normally using the remote control. I turned it on for the first time in a while, and there was an unusual fan noise at startup, but it stabilized within a few minutes and became unnoticeable. ◯ CD playback: OK ◯ MD playback: OK ◯ Radio reception: OK ◯ LCD brightness: OK ◯ Panel action: OK ◯ 4MD changer operation: OK ◯ CD/MD insertion and ejection: No issues ◯ Sound output from each speaker: OK ◯ Remote control: OK ◯ Instruction manual included (with a tear on the back) *This is a defective item and is sold as junk. Please understand this before purchasing.