[mikegett]

Your problem is deffinately the monsoon system on the speakers. I contacted monsoon to see what ohm the speakers were (or at least the rear) and they are 2 ohms. That means that when you put a four ohm speaker on to the amp you will be cutting the wattage in half. It is 50 watts max at 2 ohm, so I am going to assume that you are probably getting 25 watts max to the speaker and around seven rms. Be aware that when replacing your speakers you should seriously consider doing a amp at the same time. Your new speakers will need about three times the amount of wattage that the OEM speakers required and will not only sound worse on the head unit but can also be damaged. Very few speakers are damaged due to excess wattage. It is under powering them that causes the distortion which in turn creates heat and blows the voice coils. So in the mean time, keep the bass turned down until you get the amp. Good luck.