Charts go blank randomly

I am facing a problem and have no clue what the cause is. Charts go blank randomly (mostly on changing tab or timeframe though, but not consistently). Then they won't return to normal until after significant time and no action can fix that. 

I was thinking it might be the video card (AMD Radeon R7 360 series), updated drivers (also updated Windows), but no change at all. Then I saw that the second instance running (second account) does not face this problem. Also, some weirdness I noticed at the time of the issue: alert sounds are played later than the alert trigger, menus stay on screen and won't go away if I don't mouse over them (not selecting anything). If I close ctrader and re-open,  it will run smoothly for some time, then randomly start again. I am having a hard time trading like this.

Should I try re-installing ctrader? If I do that, will I lose the drawings of charts? Thank you.

edit: Also submitted report via ctrader menu