#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 ........

It is a permissions issue that is hard to fix. All but one USB device is greyed out. I am already a member of "vboxusers" I have already enabled and disabled USB support for the guest. I have already reinstalled the latest VBOx guest editions If running as root it all works fine Changing........

ip_conntrack: table full, dropping packet. A lot of clients I've seen have this issue, it really seems the default level is way too small. Once this connection tracking table becomes full then packets get dropped which is obviously a bad thing. One thing to be mindful of though is that 350 bytes of memory are used per entry so there is some justification for not keeping it too high. However, if you have multiple servers running or high traffic daemons........

Use "ImageMagick" which can be installed easily on most UNIX/Linux distros. Remember that it will go with the standard file listing to determine the order but I believe you can manually specify multiple jpg's in the arguments. Convert image/jpg to PDF convert *.jpg yourpdf.pdf This is a very handy and free tool. Convert DOC/TXT documents to PDF If you wanted to convert a .doc file or text........

The solution is simple but it's a wonder why VBOX doesn't address it directly? Perhaps newer versions will but you have to add your user to the "vboxusers" group and then login and logout and you'll see the devices you wanted but couldn't access are now available. The weird thing is that the grayed out issue doesn't happen with all devcies but one notable thing is the Apple iPhone especially in DFU or Recovery Mode which is an big issue for some people.........