Singlespeed & Fixed Gear - persistent loosening cone on rear hub

Here's a new one to me - my rear hub keeps loosening. I get the cones as tightened as possible without impeding rotation, crank down on the nut, put it on the bike, and everything's fine (a little side-to-side play, but nothing outrageous). Yet the next time I check it, there's way more wobbliness than I like. Today, after adjusting and tightening it last night, I did a tiny little skip and heard a noise, and lo and behold, it's wobbly again.

Hub is a Surly. I have another set of surlys that I don't think I've ever had to adjust. It's been in service for around a year, and I've only noticed the looseness in the past month or two. The wheel joined me on a January trip across the hood of a car, but seemed fine thereafter (wasn't even out of true). Any thoughts, junior detectives?

use a little blue lock tite on the lock nut and it should be fine locktite on locknut not cone mmk

This is a cartridge bearing hub, right, or are there free bearing surly hubs out there that I don't know about?

Yep, sealed bearing. I'll try some loctite on the nut, thanks.

Any conjecture on why it is getting loose? I've heard of people having surly hubs tighten up on them, but not loosening (I guess I'd choose loosening if it has to be one or the other).

its because the axle is just a straight axle and not keyed like all the 80s and suhc road hubs were with keyed washers.

For serious? Have I just been lucky with my other wheelsets, then? Hmm...
Do locknuts typically move in one direction only? Like, if I moved the cog to the other side, would it be more prone to tighten up and eat my bearings?

For serious? Have I just been lucky with my other wheelsets, then? Hmm...
Do locknuts typically move in one direction only? Like, if I moved the cog to the other side, would it be more prone to tighten up and eat my bearings?
keyed axles with keyed washers, like on all the 80s and such road hubs eliminate cone/locknut slippage.
one of the reasons why surly hubs are flawed.

yes i'm serious and i hope you know what i'm talking about

I thought pretty much all Taiwanese track hubs used a straight axle, though. And as I said, I haven't had any problems of this type with my other set of surlys. Although, yeah, there's some undeniable oversights in the design.
Well... hopefully loctite will do the job.

keyed axles with keyed washers, like on all the 80s and such road hubs eliminate cone/locknut slippage.
one of the reasons why surly hubs are flawed.

yes i'm serious and i hope you know what i'm talking about

useful little bit of knowledge. and I though I had it all figured out.

useful little bit of knowledge. and I though I had it all figured out.
believe me, the more i learn, the farther i am from figuring it all out...maybe a regression is in order..

(a little side-to-side play, but nothing outrageous). Yet the next time I check it, there's way more wobbliness than I like.

first, you didnt close your ( ). second, there shouldnt be any play, thats your problem. you should be able to get it to not play yet spin freely, it may take some work to find that point but its very possible.

have you tried counter tightening the crap out of the cone/locknut on one side before doing the adjustment?