I have a 7280 on cingular and have this problem as well. Actually it is pretty serious -- I have a under-the-cabinet CD player/radio in my kitchen, and the buzzing would come out of that thing pretty loud as long as I am in the kitchen (6 feet away). I tried to make a call near the unit (6 inches) and the noise became thunderous.

I used to have an old b/w Blackberry with t-modile and did not notice this interference issue at all. Also with my other t-mobile phone, I'll have to put the phone right next to the radio speaker to get any interference (which is faint). So this one (7280 and/or Cingular) is definitely a lot more powerful !

I have a few related questions:

[1] Do you people who have the problem have it as seriously (i.e. causing buzzing even several feet away from the speaker)? I want to know if mine is worse than normal (in which case I might want a replacement).

[2] Is the buzzing noise coming out of the affected speaker *amplified* or not? I would assume so (otherwise this is REALLY powerful and carrying it on the belt seems dangerous), but what about the boombox that is off, and the computer speakers?

[3] How do I know the frequency the BB is using for communication?

Thanks,

snehne