The original manual dedicates a full page to maintenance—advice that is even more critical today:
Even though the LBT-D507 is decades old, many units are still in use. The manual helps owners: sony lbt-d507 user manual
If you're having trouble with a specific part of the system, I can help you with: the CD changer or cassette deck Setting up the surround sound speakers Connecting modern devices like a phone or Bluetooth adapter Sony LBT-D507 Compact Hi-Fi Component System The original manual dedicates a full page to
Supports up to 30 station presets (ST-JX431). sony lbt-d507 user manual