Downloading and compiling from source to get the latest version of Asterisk is really simple with this guide.
apt install gcc make g++ libedit-dev uuid-dev libjansson-dev apt install libxml2-dev sqlite3 libsqlite3-dev
wget http://downloads.asterisk.org/pub/telephony/asterisk/asterisk-16-current.tar.gz
tar -zxvf asterisk-16-current.tar.gz
cd asterisk-16.6.2/
./configure
If you get this error change y........
#if you have nvidia make sure you install the nvidia-cuda-toolkit so hardware acceleration can be used
wget http://ffmpeg.org/releases/ffmpeg-3.3.2.tar.bz2
tar -jxvf ffmpeg-3.3.2.tar.bz2
cd ffmpeg-3.3.2/
./configure --disable-yasm
install prefix /usr/local
source path ........