Changing timer interval can sometimes break the timer. In attached example you should see timer with 1000ms interval first, then it should change to 100ms interval (every 5s). But it sometimes after this change, it stops ticking.

It seems to work if the timer is instead first stopped and then started again with the new interval. Also changing interval of timers in main thread (in multithreaded build) works fine. Maybe it did work a little better, but same issues started to happen.