Many 2018 MacBook Pros have encountered a crackling audio issue. Mine was intermittent but I found that the the crackling seemed to become more severe, with more CPU usage. I was running macOS High Sierra and attempted several things to resolve the issue but crackling audio kept coming back. The fix for my 2018
Does the 2018 MacBook Pro Core i9 overheat? There is a lot of chatter online about 2018 MacBook Pros overheating but I personally feel that there is no need for a fire alarm. Most any laptop will become warm after extended use. This is amplified by running graphics-intensive and CPU-intensive tasks. Video editing, gaming, etc.