Hi there voodoocars,
I am currently using the Lumia 830 and have to report that it (my precious) also exhibits this behavior sometimes.
It is a lot less frequent then on my Lumia 820 and feels a lot quicker, but still it will peek up its ugly face here and there.
No worries though as some of the more powerful phones also have this issue, my bet is that it will eventually be fixed or fundamentally changed in the next build of Windows Phone (WP10).
I said it before, and will repeat it here

, it feel's to me as if we are the beta-testers of Microsoft's baby-steps into the smartphone market. I know they have always been on the mobile side of thing's, but apple and Android just took it to another level. This transformation in look's, feel, usability and most of all appeal to the huge number of already settled smartphone users is a painful and agonizingly slow process.
Now don't get me wrong, i'm neither bashing Microsoft nor am i trying to be a fan-boy here, but we have to be honest and at least recognize that our beloved platform has it's/her flaw's and shortcomings, just as much as the other platforms had when growing up, and in some cases still have.
Personally i feel Microsoft has it right in the "Looks and feel" department of things even with the resuming thingy popping up once in a while.
Functionality can and will be (in my hopeful mind anyway) optimized in the future, and it's not horrible at the moment. Just lacking on small things the other players have figured out a long time ago. The pulling out of the store of some app's, the terrible relationship with Google, the abruptly taking away of the integration of the Social hub, etc.. this was not a very good strategic and consumer friendly move. They need to realize this quickly as i do NOT want to lose this platform. I just love my Windows Phone!
My 2 cents anyways lol
Have a nice day/evening/morning :wink: