teclast x98 air iii touchscreen sensitivity

I have just received my teclast x98 iii android 5 tablet and am finding the sensitivity of the touch screen a bit laggy, I tried subway surfers game and it was nearly unplayable, also browser scrolling was a bit jumpy and sometimes when switching home screens it will open an app . just feels like the screen touch is lagging behind and the touches have to be a bit more deliberate to get it to react. Anyone had this problem is there a fix or tweak for screen sensitivity or should I send it back for replacement. Thanks in advance

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Weird touchscreen issue

I have the Verizon Galaxy S3 and I have the Verizon Straight Talk sim card. LTE and all works perfect but from time to time the top left corner of my screen loses response and won't register my touch. I'll reboot the phone and all will be fine but then hours later it'll do it again. When I take my sim card out I never have that issue. Could that be a straight talk sim card issue? It's happened to me on the s5 and s6 before as well.

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