FM is a convenience, not a solution. I'm guessing your best bet is low headphone volume. Barring that, you could drop volume by way of an electronic adapter, preferably a galvanic separator, so noise wouldn't be an issue. Also, protects the N900 in case of electrical spikes.

I have line devices and N900 works fine at low volume, it's just that voltage difference makes it very hard to get consistency. Also, sound is corrected by the N900 at some point or another, and CPU is an issue.

Finally, the stuttering audio on high CPU (or if the wind picks up or a fly is airborne) is a common problem on N900, we have been at it for a while with no real, final solutions. As soon as we make some headway we'll all be happier. Overclocking doesn't help.

Given how sensitive audio is, it's entirely possible the effort of playing another audio simply stutters the music. It could be intentional, but it could be anything.

Unfortunately, there is no player that doesn't have the stuttering issue, though many have tried. I'm afraid you're stuck with either single-tasking when on audio or separate the audio player. You could try a lighter player, but frankly I'm at my eighth and no luck.

I do prefer Instinctive for looks at the very least. Hey, if it stutters, at least it looks good.

In closing, I find this unforgivable from a phone that is suppose to multitask by design. My S60 at 200 MHz had no such issues, and sacrificed everything before it choked. Makes sense to me that audio has priority over web page loading. My biggest gripe with Maemo this far.


ETA:
Fixed!