It actually applies to both PC and non-PC matches and this is just my theory from what I've experienced personally from the behavior I had in game.

It's the sound!

It's something to do with the sounds that every deployed object makes. I know in EVE for a very long time, in order to reduce lag in large fleet fights everyone would always disable the sound to prevent the client from crashing. Apparently you have somehow recreated the same problem in DUST. Only we don't get the option to disable the sound.

I'll use drop uplinks for my example. If you put down one drop uplink, it makes that nice soothing "woom woom" noise if you are withing a certain proximity to it. Well if you put down another one, it also wants to make that same woom woom noise only now it's competing with the original uplink and they are BOTH making the noise and sometime they don't mesh together well. No multiply this by like 2 dozen separate instances of "woom woom" all within proximity of you. If you step outside the area where they make the noise, no lag... Renter the area, suddenly all kinds of lag! Kinda like how in beta when you went from outside a building to inside the building and the game would glitch as it loaded the stuff it needed for the inside of the building.

So if it is indeed the sound processing choking the hell out of everything because it's trying to make 2 dozen instances of all the noises simultaneously while still running everything else, then I have a possible idea on a solution. So instead of trying to make 2 dozen noises, just make ONE. Whenever you check for proximity to any equipment to make the "noise" instead of continuing to check for others and wasting processing to do it, just set a flag to only check when not within proximity of the original object making the noise and make only the one noise not 2 dozen. Then when you leave prox of first one or if it is destroyed, then go back to original check for proximity to equipment and if true make the ONE noise again. If none, then stop.

Seriously, I don't need to hear a cacophony of 2 dozen uplinks to know that they are there. Just make one woom woom noise and good to go.

Anyways, just a thought and hopefully it gives you guys something more to go on as to the possible cause of all the lag.

That is EXACTLY what I was saying with the OP. It's all "local lag" created by 'bottlenecks' in processing due to how they programmed the sound without any limitations. It happened that way in EVE too back in the day. Only on a PS3 you cannot disable ALL of the sounds and so it cannot be worked around. Additionally, the devs cannot reliably repeat it because it's local to each PS3 and sometimes it happens and sometimes it won't. That's why you may be experiencing lag in the game and your team mate thinks you are just making it up. It's also why CCP devs believe a lot of the lag complaints to be due to local internet issues outside of their control and always ask anyone reporting this issue to first check their local networks for anything that may be causing problems.

In the end it's a combination of the sounds without limitations combined with the current voice comms in game that make the PS3 want to kill itself. And by the way, sooooo many people are raging in FW matches right now because they cannot reliably use the Team Chat Voice Channel without incurring the voice comms bug. This also nullifies any benefit we might have gotten from OS supporting EVE pilots as they can only talk to us through Team chat in FW matches.

Oh and one more thing. The bug from beta where someone drops from a height and uses the inertial dampener, but the LOUD AS HELL sound effect of the inertial dampener being active doesn't STOP. So I can hear nothing but the guy next to me with that sound going on! This tells me that if that is the case, then you probably have the same issues on smaller (quieter) levels throughout the game where you open resources for sounds and do not properly close them out when they are done. Thus causing the slow-over-time leak of memory and resources due to sound that I pointed out in the OP. Obviously not intentionally, but by the use of some simple library to create sounds, you have introduced a "sloppy" piece of code that is doing this.

In the end, I still say it's the sound!

disabling the sound in the options doesn't help, you just don't hear it, but the data is still being fed to your console

Ok, done a few PCs now after the fix, I'd say performance has probably improved (based on a very limited sample) BUT FRAMERATE LAG NOT FIXED. Gallente research facility still has framerate issues, but at least in the one match I did it didn't devolve down to slide show. So framerates dropped noticeably inside the outpost with equipment present (also persisting after destruction of equipment) but I would call the performance maybe "gooey" or shaky as opposed to the more familiar jerky slideshow feeling of that map. Some spikes also on the cargo hub map, but nothing major. The few matches have all been playable for me, but not anywhere near perfect, particularly the research facility is really only playable in comparison to what it would have been last week.