[L|0.8.657] Black Radial Flickering [SOLVED] [Ubuntu 12.04 LTS]

[butterfly]

Version Found - 0.8.657
Title - Black Radial Flickering

Summary - The video component of the game flickers in black "pie" slices of the screen.  Occasionally, the lower half of the screen flickers black.  This only occurs during gameplay (including the pause menu), but not the main menu, site selection, or crew selection.

The flickering occurred at least 1-5 times per second, and seriously impacted my capability to play the game.  Would not have continued to play the game if I did not fix this.

Steps to Reproduce -
Downloaded, unzipped, executed game .sh file as usual.  Double-checked all updates for my version of Ubuntu 12.04 LTS, to include video drivers.  Deleted all game files, re-unzipped.  Same results.  Deleted all game files and .zip folder, re-downloaded .zip file.  Unzipped again, executed new .sh file.  Problem remained.

Updated my computer from Ubuntu 12.04 LTS to Ubuntu 14.04 LTS.  Without re-downloading a new .zip file, the problem disappeared.

Attachments - Two screenshots showing the radial black flickering.

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