Just received the the amp today,don't have a guitar to play yet

It's a hissy,white noise that comes thru V 3&4. Just past the 2 on the volume and it really stars to get noisy. V 1&2 also have it but at a lower level. I tried loading it down with an old Acoustic guitar stick on pickup and still have noise. This builder is highly respected and so I'm sure the building of the amp was fine. Could it be that this is a normal part of having tubes? If so I'm not sure I can live with the noise. Thanks in advance.