Answer:
1. Psychological barriers, Nonverbal distraction, Faking attention
As Jim is not much interested in listening to German colleague where he is paying attention upon the nonverbal distraction such as dressing sense, words pronunciation etc.
2. Provide feedback, Keep an open mind, Judge ideas, not appearances
Listening barriers can be overcome if Jim, keep an open mind towards the conversation, to remain engaged, provide feedback and judge the ideas put forward by the colleague.