https://bugs.freedesktop.org/show_bug.cgi?id=76490
--- Comment #28 from Alex Deucher alexdeucher@gmail.com --- Created attachment 112144 --> https://bugs.freedesktop.org/attachment.cgi?id=112144&action=edit temporary workaround
The attached patch adds a temporary workaround until I sort out what's wrong with the higher mclk.