Youtube downloading is not supported anymore.
Download your favorite music from soundcloud using Videoder . Videoder is an android app that lets you download videos and music from Youtube, facebook, Instagram, soundcloud, dailymotion and many other sites.
Tap on the soundcloud icon to open the soundcloud website. Search for the mp3 that you want to download and tap on the one you want to download
When you open a video a red download bubble appears on the left bottom corner of your screen. Tap on the download bubble to view the download links and choose the video quality in which you want to download.
You can then choose the quality in which you want to download your music and start your download.
You can tap on the download icon on the top of the screen to view your downloads. Or you can check them in the notification panel.