D-Lab Basic Training Tube guitar amp sound fades Visual inspection reveals cause of the malfunction

Fred & Fink present, D-Lab's Basic training. This time we troubleshoot a hand built boutique guitar amp. Reported fault: After a varying period of time, the sound fades out. Sometimes 10 minutes, or maybe a few hours, but the fault has existed since purchase. After a thorough visual inspection under lighted magnifying glass, bad connections appeared on the turret terminals. The turret terminals has a dark appearance, maybe some type of tarnish. To get the solder to adhere, I have to scrape, then use rosin plus Kester solder. The process is very time consuming. If I had my guess, I'd say these terminals are low quality overseas type. Save yourself time/expense and reputation, use the best quality components at the starting line. Redo is always more time consuming. NOTE: The Dino-Lite footage was by hand, so yes, its not perfect, some shaking, but shows the detail of the connections. Remember, I'm no spring chicken.