Hiss and Hum in a system newly put together

A friend of mine recently acquired his system with the help of a friend who advised him to get following components:

Audio Analogue CD Maestro
Unison Research Integrated Amp S-6
Sonus Faber Grand Piano Speakers
Silver Audio Hush Wire Interconnects
Straightwire Rhapsody Speaker Cables

The poor guy is having sleepless nights since his system is plagued with hiss and hum. Since he is almost down under in Jakarta Indonesia, I could communicate only with email rather than physically inspect the system. From the explanation that he gave me, I could suggest to him to check his cabling and see if the system is properly grounded, secondly I also suggested to check the valves if they are properly seated and locked.

Is there anything else he should be checking?

I will send the link to this post to him so that he could try and trouble shoot his system with any help from Audiogoners.

Thanks for any help you can provide to someone who has just spent a lot of money and is having trouble from the word go.