Tee-Hee...
Being a dedicated FS 2004 Enthusiast....;)...!
My Frame rate Lock can be found here...>>>>
ALT > Options > Settings > Display > Hardware > Target Frame Rate...

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"Things" are so unbelievable simple in FS 2004...trust me!...

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Paul...G-BPLF...FS 2004...and 20 FPS at all times...

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.. for on-line, Multiplayer Flights, the FPS must be "Locked" to 20 FPS to ensure smooth flights for all participants...

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Win 8.1 64-bit. DX11. Advent Tower. Intel i7-3770 3.9 GHz 8-core. 8 GB System RAM. AMD Radeon HD 7700 1GB RAM. DVD ROM. 2 Terra Byte SATA Hard Drive. Philips 17" LCD Monitor. Saitek Cyborg X Fly-5 Joystick. ...and a Briggs and Stratton Petrol Lawn Mower.