My 20 year old Rose valve preamp has started making a 'whooshing' sound,
varies in intensity, with a steady rush of background hiss. Might it be
the valves? Everything lights up, and I've had the back off and all
looks in order.

For now, I'm using an older(er) NAD 3020 integrated amp in preamp mode.
It works fine, but sounds 'soft' by comparison with the Rose (when it
worked) - 'smooth' treble and a quite overblown bass. I did notice this:

https://flic.kr/p/rjtZuf

when I got it out the cupboard - but I'm guessing all that mess is glue?
Anything look untoward?


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Cheers, Rob