Subwoofers are a bit of a strange design. All the delicate electronics are attached to the cabinet with a massive, heavy, constantly vibrating speaker cone. To keep the electronics safe, many of the components on the amplifier circuit board are covered in a glue-like material to act as a shock absorber. Unfortunately, this material makes the amplifiers almost impossible to repair. Removing the glue material can actually do more damage to the amplifier.
Because of all this, a replacement amplifier plate is much faster and cheaper for all concerned.
If you need help with a replacement amplifier for your subwoofer, contact our support team here.