Multi-Cam Sequence within sequence - EXTREMELY SLOW

Hey,

I came accross an extremely annoying bug.

My workflow:

I created a multicam sequence (picture n.1)

I then created a new sequence from this multicam sequence, to be used for the actual multi cam editing (picture 2)

Finally, I wanted a cut-down version of the video, so I created another sequence containing the sequence from picture two. So multicam>> sequence 1>> sequence two.

The bug:

In this scenario, premiere is extremely slow. Playback is with very low FPS. Even when I'm using proxy files.

PLEASE FIX THIS.

Thank you

pic 3:pic 2: 

pic 1: