Hello,
That sounds very likely, sorry for the slightly delayed reply. Just one quick remark: According to your screenshot, he problem occurred with a LIN movement, where the speed is set in m/sec and refers to the TCP, so individual axes can go up to their maximum speed in order to achieve the tooltip speed. When you are close to a singularity, the required speeds quickly ramp up and can cause the robot to stop. With PTP movements you do not have the singularity issues and set the speed in percent, as you've mentioned.
Best,
Johannes