[seguero]

Hello again guys.
A year ago I bought this beautiful f10 63 plate but I was disappointed when i heard the basic sound system. So this year I tried to do some modifications to the whole thing and was more or less successful.

Firstly, I changed the front doors speakers and tweeters to HK speakers, adding highs to this system is a very good improvement. Then I bought and installed HK speakers and tweeters to the rear and central dashboard. The day after I put in the HK under seat woofers and an amazing thing happened, they were using all the power and everything except woofers and rear speakers stopped working.
I realised that I need an amplifier, so I added a 4 channel amp and connected the rear and front speakers to it. Done all that but after all this work, there wasn't enough bass so I put an EDGE subwoofer with a built in amp on top of that. That was the moment I decicded to look for answers because with all these upgrades the bass is stil weak. The woofer in the trunk is adding some deep base but it's below average.
I also coded the audio system to individual sound in the Bimmercode app, tried all the profiles but this one provides the best sound for my taste.

I tried turning up the bass but a weird thing is happening, when the bass kicks in or I put on a song with more powerful bass, the other speakers produce a lowered sound so I can only hear the bass but not the high sounds.

Sorry for the long story, I hope I can find some help here or a recommendation.
Thank you for your time.