Basically, In my case at least, It Is the G-sensor/accelerometer.
I have been noticing increasing numbers of these freezes on Mattc 1.5 Froyo, Mainly in Landscape, Mainly in games.
I installed 'Iron Sight' Game. (If theory is right then you should be able to use any landscape game, but please try Iron sight if possible.)
I Ran the game and it switched to landscape,
SO I PHYSICALLY TURNED MY HD2 TO LANDSCAPE.
THIS IS WHERE THE FREEZING AND LAGGING BEGAN!
On the Main menu found it difficult to press any options.
When I did manage to start a Game The control buttons were hard to press and the game was unplayable because screen sensitivity was just not there most of the game.
I Then Physically turned the HD2 around and Back to Portrait orientation, AND ALTHOUGH THE SCREEN ORIENTATION STAYED IN LANDSCAPE I DID NOT EXPERIENCE ONE SINGLE LAG OR FREEZE.
BUTTON PRESSES WERE RESPONSIVE TO TOUCH AT ALL TIMES FOR AT LEAST 15 MINUTES!
HERES WHERE IT GETS MORE INTERESTING....
I Then Turned the HD2 back around to landscape again and the Problems IMMEDIATELY RETURNED.
I THEN HELD THE PHONE VERY STILL IN LANDSCAPE AND AFTER A FEW SECONDS THE PROBLEMS/LAG/FREEZES DISSAPEARED AGAIN!!!
IN LANDSCAPE AS SOON AS THERE IS ANY PHYSICAL MOVEMENT, THE GAME FREEZES, BUT IF I KEEP IT STILL THE GAME RESPONDS PERFECTLY WITHOUT HESITATION.
Can some of you please test this theory?
A cradle/Dock would be handy for testing but it is possible to keep the phone still enough in-hand in my tests.
Use the game "Iron Sight" where possible, but use other games/apps too if you have time or inclination
Post the results below ( with logs where possible ?) Please.
After discovering the above, I did a search on XDA and found that a member called 'Hinky' and touched on this but I think I have narrowed it down.... I think
Please test and confirm (or debunk lol).