I was talking to a friend the other day who started learning Korean awhile ago and he mentioned he came across a series of listening exercises. Major blast from the past. I used those when I was learning and found them to be incredibly helpful, and free as well.
Each video is a short conversation in Korean, followed by a multiple choice question based on the dialogue. The dialogue is repeated again with Korean and English subtitles. See clip below of a sample video.
There are four difficulty levels from absolute beginner, beginner, intermediate and advanced. Each level has 20 to 25 videos. Personally I think the difficulty levels are a bit missclassified. I would label the absolute beginner as upper beginner, the beginner as intermediate, and intermediate as upper intermediate. Even in the absolute beginner series they use some vocabular and grammar that takes a few months for any learner to come across. Its an unfortunate necessity, so I recommend just trying to hear out the key words you do understand.
The video themselves are free, but some additional content like transcript and grammar lessons do require a subscription. To be honest I subscribed for like two months, blitzed through all the content and then unsubscribed.
In terms of making the most of each lesson I would
1) listen to the dialogue a few times without looking at the subtitles
2) guess what the answer is
3) try transcribe each dialogue. This can be painful in the beginning but pays huge dividends in the long run . There’s quite a lot of research on the benefits of transcription, but I guess ultimately this one is up to you. It can be quite painful
A Different Take on Korean Grammar 