sour and cold coffee from pour over

Hello, my Hario paperless pour over came and tried my first cup with sound mountain view, filled coffee up to the 1 line, bloom for 30 seconds, then started to pour a very fine stream of water in, just enough to saturate and watched it drip into my mug.... taste? Sour (a little, not terrible).... and cold. I think by the time my mug filled up, it had already gone cold. Ok so possible fixes... I did notice that it dripped faster if I overfilled the water paste the coffee grinds so that it fills the cone, so maybe that will help with temp. As for sour... from my internet searches, it seems that it has underextracted, so a finer grind. Problem is... I don't drink coffee too often (it's a treat for me, like cake), so I just get it pre-ground from a local roaster. So.... now what? I sorta thought about doubling up on the coffee, filling it to the level "2" mark, this would make it flow slower would it not? but other than that... any other suggestions? Just stick with another method (aeropress) until I can get another bag and get it at a finer grind next time?

Unfortunately, off tastes seem pretty common when you're buying your coffee pre-ground. The flavors begin to deteriorate after roasting, and the process speeds up exponentially when the beans are ground. If you're going to the trouble of using a pourover and an Aeropress, consider investing in a grinder. The Hario Skerton gets good reviews, as does the Porlex. Those should both be under $50. I have used a Hario Slim Mini, but the handle stripped out the nut on the top, and it became unusable after about a year.
If you're only an occasional coffee drinker, I'd recommend you not buy much coffee at once. Find out if your roaster will see you only 6 oz or so at a time. That's about half a normal bag, and might help you drink fresher coffee. Or, find a friend or co-worker to split a bag with.

I haven't used that set up but based on other experience it does sound like your grind is too coarse, under extracted. If you have an Aeropress and the grind works in that I would use it up that way.
Are you pre-warming your cup? IMO you should have at least 160 F water sitting in the cup for about a minute before you brew and then dump it just before you start wetting the coffee for the initial bloom. If you already are preheating you might also look into an insulated cup/mug or at least one that retains heat better.
Ground coffee deteriorates very quickly from all the exposed surface area. I always grind less than a minute before I start. Since you have relatively refined brewing methods at your disposal (Aeropress and Hario) which seem to require different grinds I would encourage you to consider buying a burr grinder. You can dial in the grind to your preferences and freshly ground really is much better than coffee ground days, even if only a few, before.

Try a faster pour. I use a Chemex 8, grind the beans (drip grind, mid point on my OXO grinder) while the water is heating. A quick bloom, then fill the funnel to the top and periodically add water to keep it near the top so all the grounds are staying submerged. Get fantastic coffee, even the wife won't drink anything else now. Think I like it better than the French Press.

THanks for all the great suggestions and tips, I will try a faster pour at "1" since it is the one I can do right away. Will let you know if it gets better.

You water temp might be playing role into it..I use water around 200 on the kettle, in my press pot..I have a hand grinder and not use coffee that's been longer then 30 minutes past grinding..

Just made one... tried the quick pour, and its better! Although there is still a very slight sour note. It will switch over to the aero until its finished.

*starts casually looking at grinders*