GVR3550, Hardware Version 1.6A, Firmware 220.127.116.11
GXV3611_IR_HD, Hardware Version 1.0A, Firmware 18.104.22.168 (Camera 1) - 720p, 2048 Bit Rate, CBR, 30 fps, I-frame interval 80
GXV3662_FHD, Hardware Version 0.3A, Firmware 22.214.171.124 (Camera 2) - 1080p, 2048 Bit Rate, VBR, 30 fps, I-frame interval 80
Chrome version 42.0.2311.90 m on Windows 8.1
Looks like the latest Chrome is hard blocking NPAPI plugins, a move that Google announced in 2013, started implementing in 2014 and seems to be getting really serious with the latest Chrome build. This article (https://www.ghacks.net/2014/11/24/how-to-re-enable-plugins-in-chrome-that-are-blocked-by-google/) shows how to re-enable NPAPI plugins. Please note that the article points out that as of September this year, this (the blocking of NPAPI plugins) will become permanent, without any workarounds. Looks like Grandstream needs to keep this in mind for future Chrome support (after September 2015).