Subaru Workshop Service and Repair Manuals

If the speakers still chatter and/or vibrate, perform the following countermeasure(s):

[A] Standard speaker, perform Countermeasure 1 & 2. 
[B] High-grade speaker, perform Countermeasure 1.

^

Sealing covers with urethane are used with high-grade speakers; therefore countermeasure 2 does not need to be performed.

How to distinguish between Standard speaker and High-grade speaker

Vehicles equipped with standard speakers use a sealing cover without urethane. Vehicles equipped with high-grade speakers use a sealing cover with
urethane.

Countermeasure 1

1)

Remove the door trim speaker and sealing cover (see figure 1, below).