Your sketch paintings are looking very good. the idea a good start for this exercise. Not too complex and managable in size. your initial sketchwork is more techy and robotic in style compared to many of the sony products in your ref page. the stero best matches the style you are working with right now. I would focus on styling your product after that. also, try and find a blance between the very small detailed shapes and larger areas with less detail. you will notice this contrast on ,any of the products you are referrenceing. Overall it is a great start, try and focus on the radio refference piece.
In the beginning i don't know this design should fit that brand, so that i drawing the four page sketch, and then, when i go to the department, my classmate told me this project should design for that brand, and i try to find some sony style in 5~10 pages. i receive your email today, and it means we have no homework last week? so that ,should i redo my first week homework? because it looks didn't fit to sony's styling .