Rock Band users discovering hardware issues?

Engadget writes:

"While we're still quite early in the game (literally), reports have started trickling in that there may be some substantial issues with some of the hardware included in Harmonix's latest and greatest, Rock Band. According to forum posts from disgruntled users, folks who've just gotten the game are having a litany of problems, from drums with no sensitivity, an always-on whammy, and sticky buttons -- but most of the stress seems to be related to the downstrum. Current descriptions paint the problem as an overly- or ineffectual strum, resulting in a pretty annoying game experience. Of course, it's early on right now, and it's too soon to know if this is a widespread problem or if it's relegated to a small production batch. We pose this question to our readers: are you having Rock Band issues?"