Need help with Z5500 center speaker is the only one that works

[dobywon]

My center speaker is the only one that is working on my z5500. How do i fix the system so all speakers work in THX and surround sound,

 

[kanewolf]

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Question from dobywon : "how to fix center speaker is the only one working"

how to fix center speaker is the only one that is working on my z5500