Deutsche Bank ( DB) doesn't seem to be having much luck with its stable of clever metals exchange-traded funds.Just look at the bank's gold product, the PowerShares DB Gold ( DGL). In the months since its January launch, investors have given the fund a cavernous yawn. Accumulated assets totaled a paltry $26.3 million by the end of March -- about where it started -- and average daily volume currently runs at an anemic 22,000 shares. In fact, it has made so little impact as a gold investment that Jeff Christian, guru of all things gold and managing director at New York-based specialty consulting firm CPM Group, said he'd never even heard of the DB Gold ETF and couldn't comment further on it. It's not as if gold investing is out of fashion. The granddaddy of gold ETFs, streetTracks Gold Shares ( GLD), picked up an additional 31 tons of gold during the first quarter, worth almost $700 million at today's prices. It brings the fund's recent total holdings to roughly 500 tons, or almost $11 billion. The question is: Why is the DB Gold ETF faring so poorly? It could be that the fund's designers at Deutsche Bank Commodity Services were too clever.