LERP player location with audio time

Im currently working on a rhythm game where a 2D character runs right in time with the music. I have to set my location according to a sequence player’s current time and have it all working except it is very jerky.

I have tried LERPing from the start position to the end point which is smooth and works fine, except that if the framerate drops everything moves out of time with the music.

I need to get the current time of the sequence player, multiply by speed and set the player’s location every frame.

Any ideas how i can make this movement smoother? Maybe a timeline? The alpha is set to a constant value which im guessing is the issue. I’m unsure though how to set my timeline to drive the alpha on the LERP from 0 to 1 every frame.

This is what i have so far…