I've been playing bass for only 3 years and have been wanting an upright for longer than that. I found my Palatino on e-bay and it arrived in great shape in the original box.
The first thing I noticed when I plugged it in is that the preamp is indeed very noisy. I also wasn't getting much sound out if it. Further reading of this thread solved that problem as I had set the bridge at the incorrect angle. Moving it towards and away from the neck while tapping it and finding the sweet spot is job one.
The second thing I did was order the Ingles SA-22 stand from Bob Gollihur. It works great and since I don't have a safe corner in my studio I got tired of dragging it into the next room and wrapping it in a blanket every time I had to set it down. Now it's right next to me ready to go at all times.

My favorite bass was a 5 string fretless but I wasn't ready for the larger scale and lack of dots. So I took an address label and cut thin strips to use as fret markers on the side of the neck. I call them my training wheels and they'll be off soon.
Once I got to where I could play the bass a bit I noticed that the G string was so low it buzzed above the 8th fret. The E string was also very high. I noted that my bridge was set a bit low in it's frame and I thought that if I slid it towards the G string it would move the string in that direction and due to the curve of the neck it would raise the G string while lowering the E at the same time.
A chance glance down the neck led to a big surprise.

My bridge was on backwards.

The steep and shallow arc of the neck was reversed on the bridge. You could see the bridge was way up on the E side and barely visible on the G side. I had installed the bridge according to the "E" that was penciled onto the bridge. There were also single and double marks indicating which side each adjuster foot belonged to.
This was a mistake made at the factory.

And it wasn't just labeled wrong. The notches for the strings are cut in reverse order. I took extra care that the E string didn't slip out of the shallow groove and turned the bridge around. The G string sits very low in the bridge but the buzz is gone and the E string is much lower.
I've got the adjusters set all the way down and I think the action is still a bit high. That may be normal for an Upright so I'm gonna hold off any sanding/regrooving on the bridge until I have a friend look at it. He's a pro musician who's got experience on DB's. I'll let him tell me if I can or should lower the action.
The "backwards" bridge is kind of interesting because I noticed a set of photos on this thread that appeared to be set up the same way. At least it looked like it was and the carved "S" in the bridge is facing the opposite way.
I've not tried the rubber under the bridge as it looks as though the pickup has been wrapped in rubber from the factory. And since I haven't noticed any tail piece buzzing I'd have to say that except for the preamp buzz I'm very happy with the bass as it arrived. So until I can play the thing with enough confidence to take it out of the house I'm happy with the way it works now.
When my wife joined the church choir and they needed a bass player 3 years ago I volunteered to give it a go. At 50 years old I can honestly say playing bass changed my life I'm having more fun than I thought I ever would.
Now if I could just find some jazz cats to start a band........