I'm learning standard Chinese and I recently realized that my listening skills are worse than I hoped. Once I hear something unexpected such as a common word but spoken with a different accent, the entire sentence becomes incomprehensible and it throws me off guard. As a result, one mistake leads to next sentences being also poorly understood.
I noticed a similar phenomenon when learning how to hear Morse code, which you practice in a way that's similar to practicing listening comprehension of a foreign language. I can currently do simple (4-character) exercises easily, but adding another one makes me feel overwhelmed and results in me remembering less (only the first 2 characters).
This makes me feel that the problem might not necessarily be related to whether I know certain words, but how I react to something unknown. Is there a way I can reduce or get rid of the brain freeze that happens when I hear something unexpected?