Audio Systems: BMW INternal amp fuse keeps blowing, sony cd player, amp fuse

Question
I am installing an after market pioneer ced unit in a 1990 BMW 525i, but the Kenwood that was in prior, the sound stopped working, but it still had power. I checked the Blaupuntk (SP) internal factory amp in the trunk and the 10 amp fuse was blown, I replaced it and each time the speakers would play for a few seconds and the fuse would blow again, I tried checking the plugs to the amp to see if there was anything that looked burnt, but all looked well. After trying again, somehow I lost all continuous power going to the radio. I tested the wires and the fuse under the hood. A test light shows ignition key power, but the continuous power wire (yellow) showed nothing. I tried running a wire straight from the battery just to troubleshoot it and the Kenwood played for a minute and the place I connected the temporary power wire to the old one burned  out the old one and it started melting and smoking. I said all of that so you would have a clear idea on what has taken place. Please let me know If you think I can run new wiring and do I have to run it to the amp or if I am installing a new Pioneer 50wx4, can I just bypass the amp and run all 8 speakers from the pioneer? How do I get my power back? Do you think the amp was the original problem? Please help! I would appreciate any info you have for me. Thanks

Answer
this same problem happend to me about 10 years ago  on a 92 535i we sold him a sony cd player
i solve the problem installing a 20 amp fuse  every 2 or 3 weeks the customer came back no audio and i will install a new 20 amp fuse  couple of months later the sony radio lost the lights on the display and was send to be repair ,factory radio was install back in the car for 3 weeks,it never blew a fuse   so the next time we install the sony radio back in the car we add  this

http://www.soundgate.com/index.php?request=product.details&categoryid=188&produc...

no more blown fusesfor a long time  1 year later the car is back  blown fuse again i replace the fuse and it blew itin a second  so that is when we remove the factory amplifier and run the speaker to the radio the sound was not the same   the sony radio didn't have the power for all the speakers

i believe the high signal from the new pioneer cd player is  
going to damage your amplifier

yes you can run a new memory wire to the radio but have nothing to do with the amplifier
i hope this help a little
good luck