The DI20 has a reputation for being noisy. Interestingly, it apparently doesn't affect all of them - I know of some pro engineers who have been using them successfully without problems. Perhaps it's a batch thing? But at less than 20 quid per unit, it's hardly worth modifying...

At a budget level, the other behringer DIs are fine - the DI100 etc. The Studiospares own brand one is pretty good - and the own brand one from Thomann looks like it's the same unit, but a little cheaper.

Or check out the DIs from Orchid Electronics. A little more expensive, but great products from a UK company that makes great kit and understands our needs. http://www.orchid-electronics.co.uk (I have no connection with them other than as a satisfied customer)