Depends on the nature of the "fizzling" sound.

Could be a grounding problem. If the sound reoccurs, try opening it up and loosening and retightening the grounding plate screws and the grounding strap to the chassis.

It could also be Q3 on the analogue board failing. If this fails, it will take the flyback transformer with it. Is there ANY evidence of video problems, in particular an occasional "wiggling" along the right side of the screen? This would be an indication of something more serious heading your way ...