melos sha-1 problems...


Hello everyone,
i've got this pre-amp recently but it has got a big problem. could you guys please help or give advice?
when the first time i hook it up i found it takes more than 5 mins to warm up and after that it comes out with a hiss sound even though i turn the volume pot all the way down. when i turn it up to around 2~3 o clock position it turns from hiss to a big "wooooo" sound, the sound is so big that i can see the speaker cones are moving... so i change all the caps to a better ones(same value) except 2 of the 6uf/250vac and change the volume pot to a DACT step volume. change the tubes to jan-philips 6922. but still the hiss is still there. the worse is that when i connect it with my other melos cd player(with melos d/a) i can hear the sound when the player scanning the cds(from the speakers) please could anyone help since i live in hong kong so not much people can help me this nor getting the caps (6uf/250vac). anyway below list is gear i'm using now.
cd: melos cdtII with melos cd player(sony mod)
pre: sha-1
power amp: aragon 4004 mkII
mon: adam anf10
power con: lightspeed 3200 mkII
all gear using bleden 18awg dbl sheilding power cable
inconnect using canare cale
speaker cables using hitachi melltone(the pink ones)
many thanks!!
georgypo
Why not give it to a reliable tech. Sounds like you`re in over your head. Changing caps & tubes doesn`t solve every problem. Test equipment & expertise are probably needed.