osx - ffmpeg avfoundation (Mac OS X) capture second screen desktop -

i use console ffmpeg, if capture first monitor, well

./ffmpeg -video_size 640x480 -framerate 30 -f avfoundation -capture_cursor 1 -capture_mouse_clicks 1 -i 1:0 -c:v libx264 -qp 0 -preset ultrafast capture.mp4

if try capture second monitor process hangs

./ffmpeg -video_size 640x480 -framerate 30 -f avfoundation -capture_cursor 1 -capture_mouse_clicks 1 -i 2:0 -c:v libx264 -qp 0 -preset ultrafast capture.mp4

my device list:

avfoundation input device @ 0x7fc74141a0c0] avfoundation video devices: [avfoundation input device @ 0x7fc74141a0c0] [0] hd-camera facetime (integrated) [avfoundation input device @ 0x7fc74141a0c0] [1] capture screen 0 [avfoundation input device @ 0x7fc74141a0c0] [2] capture screen 1 [avfoundation input device @ 0x7fc74141a0c0] avfoundation audio devices: [avfoundation input device @ 0x7fc74141a0c0] [0] built-in input [avfoundation input device @ 0x7fc74141a0c0] [1] boom2device 

but if replace output format mp4 mkv record on second monitor too! how fix bug?