You are downloading the Volume XAP file v22.214.171.124 for Windows Phone. Volume is a free and useful Productivity app: IMPORTANT: Volume does not work on Windows Phone 8.1, because the sound volume of the device can no longer be changed the way we used to do it. We're ... You can now download the offline XAP file to install & try it.
Download Locations for Volume 126.96.36.199 XAP file
Important Notice: Now Due To Unspecified Limitations, You Can Not Use The Offline XAP File To Install It Any More.
To try to install it manually from an SD card, you should choose one of the server location above to get the offline Volume XAP file, move the file to your phone's SD card and then tap 'Install local apps' in the phone's App list.