If your aftermarket deck has an internal amp, then bypass the factory amp. You need an amp somewhere in the chain. Most likely your headunit has an internal amp, so bypass the factory one.
EDIT: your headunit has a 50x4 amp built in, so definately bypass the factory amp.
1999 Red / Tan SVT
#1969 of 2760
Built 4/21/99
K&N, DMD, FMS Wires, ES Insert / Bushings, PF End Links
17" FSVT 5-Spokes
Factory Spoiler
35% Tint All Around
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