and considering i've clean booted my machine a number of times, the machine is relatively new (november approx last year) is fully up-to-date and in very very capable hands of a desktop/application support engineer. I have been down the driver route, and have tested with previous drivers for both gpu and sound card as well as all the things mentioned in the first post on this thread. There is many things i've not summarised too. Nothing stops this issue and i dare say many would have given up trying by now and either shelved the game or just stop posting about it.
I am determined not to stop highlighting this issue and keeping it in focus until we start to see some developer support for the issue because i really think at this juncture neither you, or I or anyone else visiting this forum as a customer of EA stand a chance of curing this issue.
As someone else posted, if they would build in a sound-reset feature even as a temporary workaround, this would be something. After all, as soon as you close ME:A you hear a pop on the speakers again (same as when the sound disappears) so its my guess its a hung process within the engine that is stopped. AS others have also pointed out, even when ME:A has stopped sound, you CAN still launch other audio apps and they still play sound, so the sound card isn't refusing to receive data to output as sound.
I've got a number of shelves full of older games that I no longer play, and then there is the newer games nearby.. and ME:A is the only game this fault occurs on, in fact, it is the only game i've actually had any audio related issue with. So i'm not focused on my machine, when the fly in the ointment here seems to be ME:A