AN AIRBUS 320 IN CRUISE AT FL350 HAD FLASHING CEILING LIGHTS; CALL LIGHTS; NO SMOKING AND SEAT BELT SIGNS ALSO FLASHING; WITH PA AND INTERPHONE INOP.

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ABOUT 1 HR AND 20 MINS INTO FLT WE COULD HEAR THE CABIN CHIMES SOUNDING CONTINUOUSLY. THE FLT ATTENDANTS CALLED THE FLT DECK AND ADVISED THAT THE CEILING LIGHTS WERE FLASHING ON/OFF CONTINUOUSLY. THE FLT ATTENDANT CALL LIGHTS AND CHIME WERE GOING CONTINUOUSLY. THE NO SMOKING AND SEAT BELT SIGNS WERE FLASHING. INTERPHONE COMS AND PA WERE ALSO AFFECTED. CONTACTED MAINT AND 'DD.' MAINT SUGGESTED 2 SETS OF CIRCUIT BREAKERS TO CYCLE. AFTER CYCLING THE CIRCUIT BREAKERS THE CABIN LIGHTS STABILIZED ON FULL-BRIGHT WITH NO ABILITY TO CTL. THE CABIN SIGNS (NO SMOKING AND SEAT BELT) FAILED 'OFF.' THE FLT ATTENDANT CALL LIGHTS REMAINED 'OFF.' THE PA AND INTERPHONE FAILED COMPLETELY. VERY DIFFICULT TO COMMUNICATE WITH CABIN CREW AND PAX WITH THIS SIT. DUE TO SOME WX IN ZZZ AREA; HAD TO GET UP TO PASS NOTES UNDER DOOR. FLT ATTENDANTS THOUGHT TO BLOCK COCKPIT ACCESS AND BLOCKED FORWARD LAVATORY. BTWN HIS BEING ARMED AND THE DOOR BLOCKED I OPENED THE DOOR TWICE TO COMMUNICATE WITH THE FLT ATTENDANTS. ON ARR AT ZZZ RAMP TOLD US 'NO GATE; GO TO THE BOX.' WE HAD NO KNOWN ABILITY TO PASS THIS INFO TO THE CABIN CREW OR PAX. JUST AFTER THIS THE FLT ATTENDANTS CALLED AND SAID ALL SYS RETURNED TO NORMAL ON FINAL APCH.