Still Need Help

You cold put a hundred cinder blocks under that turntable and it would not help. Your only hope in this situation will be a subsonic filter. I doubt you will cough up for a MinusK platform. This is why suspended turntables like the Sota are so important. You can kiss this stuff goodbye. 
Any wall in the house is going to vibrate to some extent. Wall shelfs might help against footfalls but not to feedback. 
The best subsonic filters are digital as they can roll of much faster without affecting the audio band. 
It is possible that a cartridge that is less compliant with a lower output might help but I would not guarantee that. There may be a less expensive isolation platform that will work but I do not know any. Any isolation feet or platform would have to be sprung to have a resonance frequency around 2 Hz.  

Try to isolate the subs on their own base that decouples them from the floor to remove the floor excitement they are creating. A good way to do this is to use a slab of stone under the subs. It is effective and relatively cheap and painless to implement.

Can you be more specific? What do you mean “vibration”? Is the sub output vibrating/energizing the room enough to effect the TT during playback, or are you getting woofer subsonics when the stylus hits the vinyl? Two different problems. 

Try plug the ports of subwoofer?

Your Rega wall support is made from hollow metal that can resonate. Putting P3 directly on it will not help alone. You need to decouple somehow your tt from the shelf. And still airborne vibrations would affect its lightweight chassis. Try to have the lid removed when listening.
G