Panasonic SA- AK 133 Music system sor...

Dear Sir ,

I am having 4yrs old Panasonic Sa AK 133 Music system.
Its having sorrounding sound function . If we are Enabling / ON this sorround sound , then entire system sound goes OFF in speakers while CD & Radio / display show working .
If we close the sorround sound function , then sound from speakers .

Can we fix up this problem and enable sorround sound again .
Pls. also advise for possible components replacements .

Warm Regards
Rohit