Found some new info. I modified the test before, and discovered that the problem happens in fullscreen letterbox landscape mode as well in some scenarios.http://www.amirai.net/ipad/r105/ipadfps.zip
This is the sprite test in full screen letterbox mode with a canvas size of 2048x1345. Works smooth: http://www.amirai.net/ipad/r105/
Lower the vertical resolution in the properties by 1 pixel to 2048x1344, and the bug happens: http://www.amirai.net/ipad/r105/2/
Also, if I load those links above to the exported versions, I noticed if I rotate the device before the page has finished loading and the blue bar under the web address disappears, it doesn't resize/adjust the canvas to fit the window. It only readjusts it properly if the device is rotated after it's finished.