i have a Pioneer sx1010 that sat unused for about 20 years at my parents house. I recently discovered it and it works fine except that there is static when changing the volume or balance. Sometimes this also results in one speaker cutting out completly. Someone suggested to me a while back a cleaning product to clean dust inside the unit on a specific part but I lost that info. If someone would be so kind as to describe the cleaning process and what to use, I would appreciate it.