Hi: I have the TX2. I purchased it second-hand and although in beautiful condition, the tone arm assembly was rubbing against the underside of the cover.
I believe that the previous owner had believed that he was locking down the suspension when, in fact, he was torqueing down the suspension springs. Being my first B&O turntable, I wasn't sure what was wrong. As a Silver member, I immediately took to studying the manual.
It turns out that the springs were way over-tightened. According to the manual, the correct height adjustment of your platter (without a record) from the surface of the aluminum deck top is 2.5mm to 3.0mm. Make sure that your drive belt is attached prior to making the final adjustment as it tends to pull the suspension assembly ever so slightly to the left. The screws are accessable from the top by removing the platter. This will require that you keep removing the platter and putting it back on to confirm the height.
I actually made 2 hard maple blocks about 1" X 1" on my table saw - one with a 2.5mm rabbit cut and one with a 3.0mm rabbit.
This allows me to set the height accurately over each of the 3 springs. I play 180 gram LP's all of the time and once adjusted correctly, I have never had a problem with it bottoming out or rubbing against the cover. It is now functioning perfectly.