Trane variable speed

Model: 2TEE3F31A1000AA

Serial: 7321T9H2V

1/2 h.p. motor.


About 3 weeks ago a strange sound was birthed from the a/c and continues every time the blower starts.
The t-stat will kick on and the cycle initiates. The blower starts and about 5 seconds in there is a pretty audible noise that can best be described as a burst of air. Or maybe even a loud click. Its really hard to tell. Im leaning more towards the burst of air sound. It only happens about 5 seconds after the blower starts.
Is this when the higher speed kicks in? Is it potentially life threatening for the blower or any other part?

I apologize if my terminology isnt up to snuff, I have not provided the correct info, or if this question is irrelevant.

Thank you for reading and replying.