Ok, so a buddy of mine that installs car audio for a living is helping me with my install and I was telling him of my problem with the sub losing kick. He shot me this email and I thought I'd share it with you.

I don't know where he got it from.. all I'm doing is passing the info:

No: TSB-09-54-012
DATE: October, 2009
MODEL: See below
Subject:
MALFUNCTIONING SUBWOOFER SPEAKER REPLACEMENT & AMPLIFIER EXCHANGE This TSB supercedes TSB-08-54-003, issued March, 2008, to revise information relating to affected vehicles and advise additional countermeasures to the amplifier. revised information id indicated by


<.PURPOSE <
Customers of some affected vehicles equipped with the Rockford Fosgate Audio System may notice the subwoofer speaker produces little or no sound, or produces abnormal noise (e.g. static). This may be due to a shorted speaker coil, caused when the following conditions are present:
^ With some audio settings and/or audio sources, the output of the amplifier may be too great for the subwoofer. AND/OR
^ Under certain ambient temperature conditions, the subwoofer may not properly dissipate heat. If you diagnose a vehicle with this condition, install a new subwoofer speaker and exchange amplifier with revised logic.
Additional countermeasures have been taken to limit subwoofer output for affected vehicles.
AFFECTED VEHICLES <
2008-09 Lancer
2008-09 Lancer Evolution Affected vehicles equipped with Rockford Fosgate Audio built prior to VIN 9U025913 (10/01/2008).
REPAIR PROCEDURE
Replace the audio amplifier and subwoofer speaker. Refer to Section 54 Chassis Electrical of the applicable service manual for details. After completing repairs, confirm the condition has been corrected.
CAUTION!
The interior components of the vehicle must be protected to prevent damage when removing the seat from both its mounting points and the vehicle. Use shop blankets to cover areas where damage could occur when removing the seat.

 

The amplifier built into our vehicles is an 8-channel digital signal processing amplifier. 2 of those channels connect to the Dual 1 ohm subwoofer in the back. Dual 1 ohm subwoofers are almost non-existent so the stock woofer can be replaced with a Dual 4 ohm or Single 2 ohm subwoofer if you bridge the stock amplifier.

Anyway, this is a DSP amplifier, meaning it is a digital signal processing amplifier. What happens is it automatically adjusts the subwoofer output depending on the music being played to make sure no harm comes to your sound system. I can literally hear it take my bass and destroy it by turning it down to the point I can barely hear it. The first few seconds of a song are nice and punchy and then it just...disappears. Now, if this is not normal then I would love to know to get my amp replaced.

 

Noticing the same thing on my 2011 Ralliart Premium! I'm looking all over for some way to fix the issue. Do I need a new amp? Or to hack the "logic" on it. Or a new sub to prevent damage or whatever or what? Really want the kick back!