Philips FA960 Intgrated Lamps

I have a problem with my Philips FA960 integrated. The bulbs around the volume control and power switch are out. I replaced them about a year ago, and they were fine for a while, but now I find that the bulbs themselves are fine, but there's no current getting to them. I've checked the wiring, but don't see anything obvious.


Anyone experience anything similar with a Philips or similar Marantz amp of this era ((1980s)?
 
They fuse by a set overload so they are rated by wattage it would not be wise to use a higher wattage ,they have a special coating on them (non wire-wound types ).


Ordinary resistors can use higher wattage's but not in this case.