1- thought so
2- ok. its probably newer (you could try using the disk which came with your mobo for the old ver)
3- its more likely new drivers.
4- it sounds like there is a usb game controller or other device which needed the rocksmith usb drivers? likely the game doesnt support higher than 16bit sound (although did you still have issues with it set at 24bit or higher?)
5- see below for sound devices
speakers - this is for your speaker 3.5mm connections on the back of the motherboard.
headphones - this appears when you have headphones plugged in to the headphone jack.
hdmi output - sound can be output via hdmi cable. this is used if you ran with a receiver/home theater set or if you hooked up to a tv and wanted sound on its speakers.
digital output - likely a spdif coax cable (normally looks like a orange ringed rca plug) for exporting audio to some theather systems, receivers and the like.
digital output optical - spdif optical cable connection. similar to the above.
mic (webcam) - you likely have some sort of camera hooked up which has audio capabilities hence why its listed.
mic (realtech) - the default audio device for when you have a regular mic hooked up.
stereo mix - this allows you to record sound exactly as it is being output by your computer speakers.
mic (rocksmith) - the usb device you installed for rocksmith is why you see this listing.
note about mics: its entirely possible to have one microphone and multiple listings for mic in recording devices. when you install specialized software (like rocksmith or webcam software) it might add in extra audio devices which need to be used for that particular program/application. for instance... i recently tried out the razer virtual surround software and it added another item to my list of playback devices even though the number of devices did not change. it does this so that it doesnt interfere/screw with the other devices and settings, so its easy to remove on uninstall and also so you can swap back and forth if need be for different applications.
missing - the line out port would be under playback devices not recording since its not receiving from a source, its broadcasting. "line in" however can be used as a source for recording however isnt often included on just motherboard audio (but is on some soundcards)
6 - it sounds to me that one or more of these things is an issue: either your motherboard has developed an issue with the front panel audio input/output, the connectors are screwed up, you are getting static from the motherboard or your front panel 3.5mm connector is shorting out/bad.
-----------------
i do agree that front panel jacks often are not all that great. its also not rare to see issues with motherboard onboard sound having crackle/static out the rear.
things you might want to try...
*if you have (or if you have a friend who has) a spare case around (it can even have other hardware in it!) you could try disconnecting your case front audio connectors and connecting the spare cases connectors up to it. how is the signal? if the other spare case has hardware in it (even better!) you could also connected your cases front panel audio jacks up to the second cases front panel audio jacks. (note: the only thing you would be swapping are the front panel audio jacks only). this will let you know if there is a problem with your motherboard output or the front panel section on your case.
if its a problem with the actual output on your motherboard.. you have three options.
- plug only the headphones or speakers in to the rear panel, one at a time. use a 3.5mm splitter but keep the volume knob on your speakers turned to off whenever you have the headphones plugged in (and you need to unplug them when done). use a 3.5mm audio switch to swap back and forth betwen the sources. its possible to wire up a device like this http

/www.frontx.com/ to your rear panel audio then mod in a switch into the front panel for disabling/enabling the connection but its a bit of a pain.
- buy a soundcard and use the soundcard output for your speakers and onboard rear output for your headphones. swap the default audio device whenever you want to go back and forth between the two.
- the easiest way is likely to use a pair of speakers which has a headphone jack on the front of them (like some logitech sets do) which overrides the speakers just like the front microphone port does. you can then unplug when done and its all within easy reach.
*if the front panel audio has the same static/issues when connected to the other pc and/or the other pc front audio jacks appear to work fine then i would say you have an additional option
- see if you can buy some replacement 3.5mm jacks for the front of your case. if you are not sure about replacing the existing jack you might be able to get a device like http

/www.frontx.com/ or another front panel device which has a mic and headphone jack and connects up using the internal connectors to replace the connector you already have. if its a busted or shorting out jack this should fix the issue (but if the static is caused from internal noise then it wont)
--------------
i placed these two seperate since they are likely the easiest options:
*instead of using the front panel audio ports you could try converting to usb. i cant say how well this device works
http
/www.amazon.com/Turtle-Beach-Advantage-Headset-Adapter/dp/B0036VO4XO but something of this nature could solve the issues with a bad port AND static from internal noise. you could then unplug it along with your headphones. when you plug in/unplug it might even automatically set your default audio device correctly .
*re-listing this one from above: you could use speakers which have a 3.5mm headphone jack on the front of them