Hi blckmag, and welcome to Elise land.
Firstly, well done for aquiring this very good amp at what was probably a bargain price, given the latest price rises lol!...I sincerely hope so!!

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And secondly, well done for finding my original 'Elise' thread, which I thought was lost in the mists of time after banned member Shaffer managed to bring about its demise!

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Thirdly, sorry to hear of your 'scratching' issue, but as
@mordy said, this is often due to poor or dirty tube pin contact, or poor cable connection somewhere. Hopefully yours was indeed just down to tube(s)...but another culprit - especially in amps that have had a lot of tube insertion/removal - can be the actual sockets. That particular design of pin receptor is prone to developing a loose connection with the pins, and which is what happened to my own amp, along with occasional others (who were, like me, avid tube rollers!!). This is easily remedied however, by (carefully) prising together the top parts of the receptor so as to reduce the increased distance between them and reinstate a tighter grip on the pins. This is one reason why I asked F-A to install better quality sockets in Euforia...but which can sometimes be a tad
too tight, depending on thickness of pins and whether nicely smooth or not - swings and roundabouts, alas!!
Lastly, I hope you will be able to find the time to peruse the other later Elise threads - I'm sure you would find some very useful and interesting information, not only about Elise but other related topics also...GOOD LUCK!!...and best wishes for many happy hours enjoying your amp, as many others have done before you...CHEERS!...CJ