Ungrounding an Amp--Any Danger?

Nsgarch: I own vdH The First Ultimate and The First Metal Screen coaxial IC's. Metal-free TFU uses a carbon fiber screen/return, which far from being especially immune to EMI/RFI, is actually not recommended for use in situations where hum is likely to be picked up, including connections to tube amps -- a drawback in an otherwise outstandingly high fidelity design that I can personally attest to. TFMS was introduced to help in just those applications, by virtue of (as the name implies) an additional metal-mesh screen layer. vdH also makes several other models employing coaxial construction for analog use, both all-metal and metal/carbon hybrids (The Bay, The Name, D-300, The Source, The Well, D-310, The Combination, and MC Silver are all coaxial designs intended for audioband signals). WireWorld is another company that makes coaxial analog IC's, using a variation where the inner and outer conductors are both tubular. (It might be worth adding that, although coaxial cables by definition have their screens connected at both ends, WireWorld still claims these models are audibly directional due to grain orientation.)

By all means, contact the factory or authorized dealer/tech about the problem. Until then, just put up with the a little hum. No doubt this can be repaired or corrected. Just my 2 cents.

Apart from what's already been said, I have found that not grounding my amplifier yields better dynamic range.