To be successful in learning a language, it is very important to immerse oneself in the language. Moving to the area of interest and listening to native speakers is very helpful. However, since language is a dynamic construction with almost a life of its own, it can also be confusing to hear the language in practice.
One reason for this is regional dialects. German, which I am currently learning, is full of many dialects, to the point that sometimes native speakers from different parts of the country can barely understand each other (again, the poor Bavarians come to mind; no one outside of Bavaria reports ease in understanding them).
I'm still very much a beginner in German, but I can hear some of the differences in the regional dialect of where I'm living, in the Rhineland-Pfalz. For example, speakers here say that "ch" sound more like a "sh" sound where in Hochdeutsch (the "school book" type German), that sound is more of like the sound of "loch" in Scottish. For a native English speaker, the "ch" sound from Hochdeutsch can be very difficult to learn and get right. Even when a person feels that she has it perfect, someone will of course correct her (not that this has happened to me or anything ;) I am tempted to adopt my local area's "sh" sound, such as saying ich like ish, but then again I would prefer to speak what is accepted as "standard" German. Plus, my very patient German teacher worked so hard with me to develop the "ch" sound that I feel that it would be best to put it to use.
Another regional sound I've heard is what sounds like "nay," which confers the negative. People use it instead of the traditional "nein" for no. I was curious about this; after all, in German, there are different ways to express the negative: nein, nicht, and nicht. I asked the teacher from the German class I am taking. She said that "nay" is part of the Pfälzich regional dialect and it's like saying "nein." I asked how to spell it and she noted that there are different ways but she suggested "nä." She said it's also common for people to say it like "nä nä nä."
In contrast to all the no no nos I've heard, there is also the common "ja ja" that people here say, which is like saying "yeah, yeah" in agreement. It has been interesting to see the actual language in action, for sure.