I had the same problems you all mentioned (flashes, sound and video stuttering, random ADS, pinkish square out of nowhere, grenade icon when using killstreaks, etc) last night before updating the drivers (what I just did but, as far as I could see here, will not help). In fact, I found this thread through a Google search using some of these symptoms, as I was worried it could be something wrong with my rig (which it's not, fortunately). So, It's not the driver, it's the game and the (complete lack of) QA and testing before launching a new season. It's been like that for a long time, even before they started trying to push Cold War and now Vanguard down our throats (together with not changing the available maps from season to season), although it's worsening each season.
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The fact is that COD MW is a fantastic game that they are trying to kill, so they can sell the newer ones. The funny thing is: I bought Cold War during pre-sale, but couldn't stand the cartoonish look (too clean), the sniper-friendly game (giant maps with small players shooting from afar), the muffled sound (are the players using slippers? Sound is a HUGE part in MWs strategy and awareness), etc. I basically played for a few hours before going back to COD MW for good. So, when Vanguard came out looking strikingly similar, I didn't even try. And I don't like Warzone, I'm basically a DM maniac, especially for the smaller maps, so this "integration", for me, is a hassle and not a solution.
Now, let's see if the new MW (which I really hope will be from Infinity Ward) will return to the quality and attention to detail of COD MW, and with a better QA team. In the meantime, let's see how long they take to fix these ridiculous problems.
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