I had the same problem as well, but it did go away somehow on its own. Try to do what Lobbert suggests: unplug everything overnight and try again the day after. After I did that, the problem went away - I did contact Two Rock, and Chad told me that had the problem persisted, a faulty tube was most certainly to blame.

Let us know how it goes, but by all means contact Chad at Two-rock, he is really a nice chap and will advise you very promptly,

Best of luck.