Unusual probelm with my turntable

Check the connection from the cartridge to the arm.

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.

And you posted this in the speaker forum, why?

Shakey

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.