Rewinding/fast forwarding can render playback incorrectly

[CreeperPookie]

Describe the bug
I recently discovered the frame-by-frame playback mode, and now I don't know how I lived with page-by-page before lol; however, something I noticed is that when rewinding/fast forwarding with playback paused it displays the marker as tick-by-tick instead of by frame, which is not nearly as smooth (even for songs with a high BPM/tickrate)

To Reproduce
Steps to reproduce the behavior:

1. Open NBS (no pun intended)

2. Go to the playback settings within NBS preferences and change the marker mode to Frame by frame, and save the settings

3. Create or open a song with at least one note at the end of the visible layer field (such that the play bar would have to scroll against the note field when it reaches it, like the below image)
   

4. Starting from tick 0, without playing the song fast forward playback until the last note is forced to scroll into view and observe the abrupt smoothness change

5. Optionally, rewind the song directly after (again without playing the song), and observe how the song instantly snaps back to smooth when tick 0 scrolls back into view

Expected behavior
Assuming the user has the frame-by-frame mode enabled, I would expect NBS to move the play bar smoothly regardless of whether the song is playing. However, given how deep the rendering code can go, I understand that actually accomplishing that might not be easy.