Interesting. I was half way expecting to hear the sound the platter braking can sometimes make but your sound is more of a scraping. 
What do the stylus and cantilever look like while the record is playing...regarding the suspension of the cartridge?  Do the stylus and cantilever stay firmly above the vinyl or do they appear to bottom out occasionally?

-sonavor

Is the sound consistent with the carriage motor operating?

Martin

the cart should be OK, it has only 10 hours on it, I bought it from Soundsmith, it's an SMMC2 in the wooden box, it looks normal, no bobbing up and down, just to make sure it was not the cart I swapped it over for my hardly ever used MMC1 (for special occasions) , and it is the same background noise, like the wipers are on in your car 

I played a record with the volume knob really low, and I am pretty sure it is the platter slightly coming into contact with the sub platter rotor, I am going to take it all off and put it all back again tomorrow, it seems I was not diligent enough with this in the very beginning :-) 

Yeah, it sounded like scraping.

I would operate the Beogram when you have it in the service position. You will be able to see things better from the sides. The suspension won't be suspended so just make sure you are on a good, sturdy surface that won't get bumped. You can run the Beogram platter motor with the platters in place or just the black sub-platter to check the rotation. Just don't try and operate the platter with the subplatter removed (i.e. only the hub). It doesn't like that...you can blow a fuse.

-sonavor

I just read Martin's post above. The sound could indeed be from the tangential drive motor. It typically advances the tonearm assembly every revolution. 
You will be able to tell more easily playing a record with the Beogram in the service position.

-sonavor

Is it consistent with the platter rotation?
Record scraping on the surrounding surface (suspension set too low)?

Martin

yes Dillen, but it must be scraping on two high spots, as the noise can be heard every second, so on a 33 rpm record, there must be two high spots I would think :-) 

the more I listen the more I think this is it !