freezing

Hi all When surface is detached from my dock, running on battery with surface keyboard attached and also wireless Logitech USB mouse - I experience issue with surface momentarily freezing up in intervals. No issues if its on its own with surface keyboard and also works fine when its docked...

Contacted support many times, they are useless gibbons. I have had my surface pro 4 for about 8 months, it was fine at first, but the last 6 months I constantly get screen freezes. These last between 3 seconds-30 seconds and is extremely frustrating. I've done 2 clean installs of windows...