Hear me out... buy green Scrub buddies pads from the dollar store. They are a thinner version of scotch bright pads (because scotch bright are too thick). Open up the drivers and cut a piece and put it in there. I did it on my T60rp and it helps control the reverb in the cup and smooths the sound a little. It will help get rid of the plastic sound of the T50rp.

https://www.dollartree.com/ccstore/v1/images/?source=/file/v8103956897414892492/products/237252.jpg