[SDL2]-Windows Speed OK-Linux Speed Slow?

Hi,

Have a strange issue with my open-source SDL2 game.
On Windows 10 Pro 64Bit native the game runs full speed.
On Linux Mint 18 MATE 64bit native the game runs significantly slower compared to Windows?

You can download the game with full source code at below URL link:
http://16bitsoft.com/files-V2a/PDHSE-WinLinux-Beta.zip
Game includes a makefile to build on any Linux.
Game requires:

  • G++
  • SDL2 + dev
  • SDL2_Image + dev
  • SDL2_Mixer + dev
  • SDL2_TTF + dev

Game was tested on same desktop for both Windows and Linux.
Desktop is mid-range and has:

  • Intel Core i5 3GHz 4-core CPU
  • 16GB RAM
  • nVidia Geforce GTX 750 Ti 2GB GDDR5 PCIexpress GPU
    (on Linux the nVidia proprietary display drive is installed v. 361)

I don’t know how to fix this performance issue on Linux.
Any help would be appreciated, thanks!------------------------
JeZxLee
JessePalser <AT> GMail <DOT> com
16BitSoft Inc.
Video Game Design Studio
www.16BitSoft.com