Unusual probelm with my turntable

Thanks for your response Elizabeth. My system is just entry-level, the turntable is a Pioneer PL-A45D attached to a Musical Fidelity phono stage, Dared integrated amp and Monitor Audio speakers. I can hear the buzz from both channels.
The shop that installed the cartridge tested the unit when I came to pick it up and it was quiet. I was worried on the drive home because the roads were a little bumpy and I could see the table bounce up and down and I thought that something might get loose. I will take your suggestion and look at the wires of the tonearm.

And you posted this in the speaker forum, why?

Shakey

I was worried on the drive home because the roads were a little bumpy and I could see the table bounce up and down and I thought that something might get loose. I will take your suggestion and look at the wires of the tonearm.
Rangefinder (Threads | Answers | This Thread)

When transporting a turntable, the platter needs to be removed so the bearings don't get damaged. I'm sure this wouldn't have caused the problem your having though. I mentioned it so anyone reading this doesn't transport one around and damage theirs. It would cause a low frequency rumble sound through the speakers if they get damaged.

Check the connection from the cartridge to the arm.