Hi fellas,

First of all, I wanted to say that it is quite a nice forum the you've got here.
I've read about everything in this forum there is about the DSP and how to upgrade from the non-DSP amp. But I still don't know what I'll do.

Here's my situation.
I have an 2003 E39 540i with Hifi Professional, nav, 16:9, cd changer, TV, BM54, Bluetooth (even the little button for talking to that lovely lady works).
From what I've read, there's no difference in the navigation and sound system between the E53 and the E39, so I thought I might post my problem here.
Since like a week ago the sound in my car doesn't work properly. The navigation system incl. sound works like a charm, but whenever I switch on the cd, radio, or TV a terrible sounds comes from the speakers. It is already very loud, when the volume is one tick above 0. Interestingly, when you change the cd or the track, the sound disappears until the next song would start. Now, if you're mad enough to turn the volume up, you'll hear the sound of the cd or radio very low, while the noise becomes absolutely unbearable. I don't really know how to describe that sound, but whoever of you guys has ever tried wringing out a cat will know recognise the sound in my car.
Now, I don't know what's broken in my car, but I guess it's either the amp or the BM54 radio unit. (Please let me know, if you know what it is)
So, I decided to exchange the amp. So instead of buying the same one again, why not take the DSP?
I still have an old amp and a sub at home, which I'll have installed, when everything's up and running.


Shall I buy the DSP amp or the BMW hifi amp?

Can I use any other non-BMW amps instead of the 2 of them?

I hope you'll be able to help me out. Thanks guys.