Due to Rust's fearless concurrency, every time I have to add a new instrument, I either have to make a copy of the entire track to add it, or temporarily borrow

Due to Rust's fearless concurrency, every time I have to add a new instrument, I either have to make a copy of the entire track to add it, or temporarily borrow the bass from the guitar track, which leads to tiny jumps in the audio. Notwithstanding the need for unsafe when I want to put the amp to 11.