Splashing stinky wine without a simultaneous copper addition can encourage the development of disulfides that tend to smell even worse.
Splashing the wine alone oxides H2S and mono-mercaptans that can form disulfides which are more chemically inernt that mono-mercaptans or H2S.
If you're not sure which you have, you can put a shiny penny in a glass of wine and swirl, you should notice a decrease in the stink almost immediately.
If you don't notice a change, you probably have disulfides and you'll need to either treat the wine with Ascorbic acid (vitamin C) followed by Copper, or just drink the wine when you have a cold and can't smell it.
A 25 ppm Ascorbic acid addition will reverse the disulfide formation so that your Copper can do the trick.... you should wait 24 hours for the Ascorbic to do its work before adding the copper.
Copper can be added as Copper Sulfate or by collecting shiny pennies or a copper pot scrubber (looks like copper steel wool.) Adding metallic copper means you won't know how much you're actually adding, but not a concern if you're not making commercial wine or not leaving the copper in contact with the wine for long periods of time.
Nutrient additions are the best prevention for off-aromas, but not fool-proof.
