Hi,

Your question is very tricky. How to shorten the length of a song?

Suppose your song is of 4 minutes you got two methods you can do it.

Method one, just drag and drop your song in Magix Music Maker arranger. Then put cursor at the start click mouse and drag to right as much as you want. This will reduce start part.

Other way, put cursor at the end click and drag towards left as much as you want, it will reduce end part.

Method two, what if you want some middle part or from here and there. Refer image below.

No.1 showing you drag your song on arranger look yellow square and red thin line that is your cursor point you want to Cut on computer Keyboard press "T" and audio will be cut.

No.2 Now look at the cursor position click "T" it will cut again. It will complete your cut or trim the start and end part. Part cursor at the part you have just cut and click Delete or remove that part will be deleted.

No.3 Centre part is empty you got one front part and back you should adjust by dragging from right to left as in image or you could also drag from left to right to align all parts.

No4. Look at the fourth part your audio final length.

Now compare the first and last you will see difference in length. Refer image and try to play as much as for practice.
 

If this is not what you want then sorry for wrong answer.

Thank you

 nihon94