You may be spot on, as the video stuttered when the call came in just a little bit, because the phone ran still at 850MHz, while it was stuttering qute heavy after the call, because it was temporarily locked to 600MHz then.
I was first testing the overall behaviour/performance and i wanted to know what really happens if you work or be entertained while a call arrives.

@michaaa
They look sweet! Post back when you've go thtem paired.

@Hurrian
I think the cables on that page are audio separate female L & R to single male 3.5mm, not audio-in-female + audio-out-female to audio i/o male. Therefore, audio-in would not be possible even though audio had been separate from video. Like your thinking though.

@5spdvl
Interesting to know. So, apart from trying to handle an extra task, the stutter is propbably because of a forced change in speed, right? Interesting.
Why is tv-out required with sound i/o? Well, when tv-out isn't for tv! As good as it is to have a h/w kb and touch screen, for word processing etc a mini office office is required: tv-out to a pc monitor and input through a BT kb & mouse. This still leaves the audio to take care of. The best suggestion so far is to use something like Nokia's BH-905.
Can anyone think of a better idea?
Also, is there likely to be any interference b/w BT devices?

I am quoting myself, am i ******ed???
The speaker are returnedt back, because they sent me the cable-connected pair, so please stay patient.

Just a year later, i ordered a pair, again, as the first dealer could not deliver the wireless version.
They look great, pair easily with the n900 and my Lenovo X60T, later i try with the desktop...
The sound is great! There is also an option to have them connected wired, which might save battery on the N900 side. Note please that the speakers are without battery, the are 12V trafo powered.