If it is ticking it is trying to start , discovering that it is not powering up properly and shutting down for safety, then repeat of the same process. A short on any supply line anywhere in the set may cause this. It's time for a technician. I will say that it should not be an expensive repair. A shorted flyback transformer may be a little costly but is the set had a good picture and everything worked before this - I would say it is worth the expense.

Here is a link that might be useful: Electronic Repair & Schematics