Mystery noise - no solution?

Ok, this is driving me nuts.

I had a noise on my Clio 200 Cup. It sounded exactly like a knackered thrust release bearing, but went away when I pressed the clutch. So couldn't be that. Thoughts tunrned to knackered input shaft bearing. Changed gearbox and clutch for a good 2nd hand box and new clutch. Noise still there, ruling out both clutch release and input shaft.

Thoughts then turned to a weird vibration, despite it sounding like a bearing. As 'luck' would have it, the exhaust broke, and it occurred to me the noise could have related to that, albeit in a weird way. New exhaust. Noise still there. Argh! And it's not a wheel bearing (noise goes away when clutch depressed). And it's nothing to do with suspension, all new or recent. Latest suggestion is it might be a loose washer on a 'captive' nut relating to the wiper motor, but I think the noise comes from,lower down on the passenger side.

ETA: Noise sounding like a rotating knackered bearing. Goes away when clutch depressed, present in all gears, increasingly intrusive with increasing revs. Gearbox, clutch, exhaust etc replaced, noise still there! Pockets empty, brain fried - help?
 
Check the bearing in the driveshaft on the drivers side?
And the crank pulley? May be to do with floating on the crankshaft?
 
Had similar in mine and it was the clutch slave (thrust bearing, part of the same thing). Noise was present when clutch was out, in gear and in neutral, sort of like a belt squeal/squealing noise. Disappeared as soon as any pressure was applied to the clutch. Ended up having both the clutch and slave replaced due to the labour involved.