monitor arm keeps tilting down

SIIG Dual Monitor Desk Stand for 13" to 27" Monitors

j5create Ergonomic Dual Monitor Mount, JTSA102

Refurbished: AVF Desk Mount for Flat Panel Display 13" to 27" Screen Support 33.07 Black Manufacturer Refurbished

Allsop® Metal Art ErgoTwin Dual Monitor Stand in Black

Ergotron Mounting Extension Polished Aluminum

Mount-It! Long Extension TV Mount, Dual Arm Full Motion Wall Bracket with 36 inch Extended Articulating Arm, Fits Screen Sizes 42 to 90 Inch, 176 Lbs.

Amer AMR6S32 6-Panel Monitor Stand - 26" to 32" Monitors

Mount-It! Full Motion TV Wall Mount with 39 Inch Long Extension Arms, Heavy Duty Dual Arm TV Mount Fits 65 to 110 Inch TVs & Fits 16 and 24 Inch Studs

Mount-It! Lockable Anti Theft Tilt TV Wall Mount, Locking Bar Security Wall Mount fits 32" to 55" Flat Screen LCD LED Plasma TVs, up to 99 lbs.

Tripp Lite Safe-IT Desk Mount for Monitor HDTV Flat Panel Display Black

SIIG High Premium Aluminum Wall Mount Single Monitor 17" to 34" CEMT2L12S1

Monoprice 2-Segment Wall Mount For Monitors Up To 27 Inch | Adjustable Gas Spring - Workstream Collection

Fellowes Office Suites Laptop Riser Plus

Peerless-AV® SmartMount Flat Wall Mount for 10" to 29" Displays SF630P

Ergotron Neo-Flex 97-589 Wall Mount for Flat Panel Display Black

Ergotron LX Dual 45-492-224 LCD Up to 24" Screen Adjustable Desk Mounting Kit

StarTech Monitor Mount for Two Displays - Up to 24" Screen Support

Amer Networks QUAD MOUNT SUPPORTS 4 X 24 QUAD MOUNT MAXIMUM OF 24IN

Ergotron WorkFit Dual Monitor Kit White 97934062

Ergotron DS100 Series Freestanding Dual Monitor Stand 33091200

Mount-It! Portrait Low Profile TV Wall Mount for Vertical Mounting of Displays from 37" to 75", Anti-Theft Design, Tilting Menu Wall Board Mount

j5create Ergonomic Monitor Mount, JTSA101

Peerless PLCM-UNL-CP Solid-Point Flat Panel Straight Column Ceiling Mount -225lb

Amer Mounts Dual Monitor Vertical Stand Mount - Max. 32" Monitors