Yocto Project/Qt WebEngine: Quicknanobrowser Stucks when Loading page

[Charles C.]

I have successfully compiled Qt5.5 WebEngine and its SDK to compile the quicknanobrowser sample to my i.MX6 board in Yocto Project. http://doc.qt.io/qt-5/qtwebengine-quicknanobrowser-example.html

These are the PACKAGECONFIG I used

PACKAGECONFIG_append_pn-qtmultimedia = " gstreamer010 gstreamer alsa"
PACKAGECONFIG_append_pn-qtwebkit = " gstreamer010 gstreamer"
PACKAGECONFIG_append_pn-qtbase = " sql-sqlite \
                                   gstreamer gstreamer010 \
                                   accessibility alsa \
                                   examples "
PACKAGECONFIG_append_pn-qtwebengine = " ffmpeg libwebp opus vpx "

However, when I execute quicknanobrowser, the loading bar will go to the middle of the page and stuck there.
the browser stuck like this
Could someone tell me what is going on here? What do I need to fix?

Another question is for HTML5; In my last version, I could play youtube videos. However, there will be no sound. What do I need to add for HTML5 video to play with sound?

[173210]

@Charles-C. I have the same issue in Buildroot, but no solution :/
http://forum.qt.io/topic/67077/qtwebengine-doesn-t-work-on-embedded-linux-on-rpi