Spoken Spanish - very hard to understand?

I think spoken Spanish is pretty difficult relative to other languages. I spent four years learning Spanish in high school, and even though I could read and write pretty proficiently, I must say that my listening is sub-par. I currently work in the Department of Spanish and Portuguese at my university, and I'm exposed to Spanish from Spain, Mexico, Argentina, Ecuador, etc. and regardless of which dialect it is, it is still difficult to understand.

On the other hand, I took one semester of German in high school and I feel that my comprehension of spoken German after one semester is much higher than what my Spanish comprehension would be if I had taken Spanish for only one semester.

In addition, I have been self-teaching Mandarin, and I can say that I can understand spoken Mandarin with more ease than Spanish.

I don't even understand why Spanish is so difficult for me. Maybe German comes easier for me because I speak English, and maybe Mandarin comes easier for me because Vietnamese is my native language.

It's all about the accents, you have to get used to one of them, not a bit from all, I myself got used to the American accent and to be honest it is quite difficult to understand an Englishman speak, let alone a Scottsman or Irish.

I have the same problem and I must say it is not the accents, at least for me. I have only ever learnt European Spanish, and yet I have problems understanding it (and other versions also to varying degrees, but only slightly worse than ES even though I have never concentrated on them). I have never had similar problems in other languages, where once I get down the words I can understand when they're used in normal conversation. Spanish on the otherhand I will listen to something (often in normal relatively educated speech) and understand little, then ask someone and find out that I actually knew all the words used but couldn't make them out.