Hi, I've recently purchased a Panasonic SC-HTB690 soundbar and subwoofer. It looks like it should be straightforward enough to set up, but there's a small note in the instructions which reads "The speaker protection cover is attached to the speaker unit inside the subwoofer. Remove it before use." It doesn't go into any other detail on what this cover looks like or how to access it. The subwoofer unit is all screwed shut and I don't want to go taking it apart (which would seem unusual for a general consumer product like this) without explicit instructions to do so. I've had zero success on Google, and Panasonic's customer services are apparently closed for the bank holiday. I was hoping to have it up and running by tomorrow, so any advice would be massively appreciated.