The FIRST step in troubleshooting an AV system is to

The first step in any troubleshooting process is to clearly identify the failure symptoms to understand the nature and extent of the issue. This step is critical as it guides the entire troubleshooting process by providing a clear description of the problem.

CTS Technology Specialist Reference

CTS materials on troubleshooting stress the importance of identifying symptoms accurately before proceeding to diagnostics, which helps in forming a systematic approach to problem-solving.