Why the woofer moves badly when playing certain LPs

Hello starbusters,

That is a classic example of a bad record. If your problem is only with certain new records, and does not happen with old records, then very probably your system is ok. That to me looks like a pressing error of the record. On the video, towards the end, it is obvious that record is warped... Bad production of the record mechanically... Not much that you can do there...Subsonic filter may help, but only to a certain degree...
Hope this helps..