You can manually trim the audio with Audacity. Audacity can remove Clicks and Noises automatically, but I'm not sure if it can trim automatically (with Nyquist plugin called Trim Silence it is possible).
Audacity is a free, easy-to-use and multilingual audio editor and
recorder for Windows, Mac OS X, GNU/Linux and other operating systems.
You can use Audacity to:
Record live audio. Convert tapes and records into digital recordings
or CDs. Edit Ogg Vorbis, MP3, WAV or AIFF sound files. Cut, copy,
splice or mix sounds together. Change the speed or pitch of a
recording. And more! See the complete list of features.
EDIT: Possible duplicate can be found here...
In Audacity there's a Nyquist plugin called Trim Silence, download it
Other possible solutions(from the above link):
mpTrim & dBpoweramp Music Converter (dMC)