"Sometimes I Just Don't Know" by Squeaky, What What, and Roadwork.

Look, hey, look, see

Now I don't know what's goin' on, but I'm trying to figure it out

I'm just holdin on (?) to keep up my head up high

And if I do that, then I'mma make it out alright

And If I don't, well I'mma just try to stay tonight

And I can't, then I'mma just get down on my knees

And pray that he can take care of me and make everything all gravy

And if he can't, well then I guess it's just

Something that I gotta do to keep me tellin' (?) me to you,

And if you don't understand then I'mma say it again

"Sometimes I just don't know..."

More Reddit comments: http://reddit.com/r/videos/comments/...     

"I've been a musician for most of my life. Every once in a very great while, something like this will happen. Very rarely is it caught on tape, but you're right - it's one of the most uplifting things in the world, to walk into a room, or up to a random guy, and suddenly be making a magical sound that only you two guys can make. No other 3 people in the world would have made it sound like these guys did. That's the magic and the beauty of it. Usually, moments like these are just lost to the universe. They're done once and then they're gone. These guys are lucky that this will live forever in this video - that's what you hope for, but usually when you set out to record magical moments before they happen, they don't happen. So these guys are lucky. We're all lucky."

I have the same feeling -- this video has a spontaneous quality that seems rare. 

"Usually moments like this are just lost to the universe."

Watched it again. Even better the second time.

hot damn! that was awesome! what joy!!

Yes, it's a good reminder of the random joy there is in our world. I love that.

just found out these guys are recording a single now.  the magic of the internet!

Oh wow. Did they post anything new on youtube or did you see an article about them?

actually, it was comments from this video on youtube!

they were on jimmy kimmel...

one thing leads to another! (but i gotta say, nothing will beat that first time.)

#t=11

They're still quite good even though it's clearly rehearsed.

You're right that the first time seemed very magical. 

The whole band joining in at 5:15 was a nice touch.

I still don't know their names other than "Jam Session Guys".

i liked it when the whole band joined, too. but i was also relieved when they left the three guys to end it.

their names are jesse (guitarist), howard (vocalist), and ron (rapper).

the youtubers HATED it when juicy j joined in and started rapping about hot models!

but daaaang, that guy in the fedora can really sing!  he was great.

Agreed about Fedora guy. I can see why you tubers would dislike the Juicy J pandering.

So do Jesse + Howard + Ron have a name for their group?

3RG (three random guys)

Thank you! I updated the title and found this interview with Jesse Rya:

texas is indeed a musical place.  :)

Is his style of music popular in Texas?

very.  lots of guys singing on the streets with lovely voices and acoustic guitars.  a little blues, a little rock, a little country... all mixed together.

Sweet -- very Jason Mraz.

Jesse Rya has a Twitter now too: https://twitter.com/jesse_rya