Voice speed issue In Premiere Rush

On two different iPhones 7 and 7 Plus during a training session today. I've had issues with the voices speed while editing. Without any reason, and without changing any speed settings, speed seems to change when playing different projects : the voices sounded faster or slower than reality. Projects used 25fps rushes. Every time, I've had to quit and relaunch Rush to solve that issue and reopen project with the right voices speed.

Title edited by mod