Okay, let’s calculate this. David has a broad range of skills, but they are mostly in the audio domain. He’s not a software engineer or a product manager, which are typically in higher demand and pay more. His certification as a Sound System Designer from SYNERGETIC AUDIO CONCEPTS INC. is a plus, but it doesn’t significantly impact the rate. Location is Blaine, Washington, which is not a major hub for the audio industry. Considering his skills and experience, I’d estimate his rate to be around $100 per hour, which is on the lower side for an audio professional. However, this is a rough estimate and may vary depending on the specific job requirements and industry demand.