All modern laptop computers have LCD screens.
LCDs are immune to interference from magnetism.
Your laptop may have display screen problems, but the chances of them being caused by magnetism from the speakers is virtually nil.
Last year I was shopping for a larger LCD TV and went to Sears to check out their sale and the one I was interested in looked terrible.
The saleskid, with a totally straight face, told me that the pitiful image quality was due to the “magnetic interference of all the other TVs on display.”.
And I when I basically said “Oh, BS!” he actually argued the point for a good 15 minutes.
I left and went elsewhere.
Wound up with a nice Sharp Aquos 52” I found on clearance at another store, instead.
Truly, I don't care if they think aliens caused the screen aberrations, so long as they fix it.