[Q] Touch screen and audio boost Huawei ascend P1

Hi folks,
I'm only posting this because I wasn't able to find by myself a solution to my issue.
I have a Ascend P1 running ICS 4.0.3, and while the phone is amazing (much better than my previous Vodafone Smart II :silly:), it has two issues that really bother me, first is the touchscreen not being calibrated correctly, I'll try to describe it properly.
In the middle of the screen everything is fine, but towards the bottom and top edges the touches are not exactly where my finger is, at the bottom the touch is registered a little lower from where my finger actually is, and at the top it's the inverse, the touch is registered a little higher, and this "offset" increases as the touch aproaches the edges of the screen, kinda like the sensible area is smaller than the screen but is mapped to the whole screen.
And the second is the audio volume, it's too low with the headphones.
A couple days ago I tried a Jelly Bean rom (supposedly from the manufacturer) and this two issues where gone, but on the other hand brought some others that are not the case right now.

So the question is, how can I address these two issues?

Thanks in advance.