Act as an audio engineer specialized in home recording. I want to improve the sound of my videos, podcast, online classes. My budget is amount, I record in room description: size, flooring, windows and I currently use current gear. Deliver in this order: 1) A diagnosis of the 3 most likely problems in my room, such as echo, background noise or electrical hum, explaining what causes each one. 2) DIY acoustic treatment using cheap materials, ranked by value for money, telling me where to place each item. 3) A gear list within my budget, with price ranges and the specific problem each item solves. 4) A recommended starting setup for gain, mic distance and input filters. 5) A 6-item checklist to run through before hitting record. Explain every technical term in one simple sentence. If my budget cannot fix everything, tell me what to prioritize first and what can wait.