[Fix] Fixed issue with interference not disappearing as it should.

src/space.c

@@ -628,6 +628,11 @@ void space_init(const char* sysname) {
       }
     }
   }
+
+  /* Clear interference if you leave system with interference. */
+  if(cur_system->interference == 0.)
+    interference_alpha = 0.;
+
   /* Reset player enemies. */
   player_enemies = 0;