DS90UB941AS-Q1: screen shake when using external clock

Hi Expert,

Our customer use 941 +948 in their project. Previously 941 uses DSI clock as input clock and it displays well. Then they use external clock as REFCLK which is generated by CDCE913-q1. The display shakes. They only change bit0-1 from 00 to 01 in register 0x56. Is there any more register they need to change correspondingly? 

For 941, they configurate:

1. reg 0x17-->0xde;
2. reg 0xc6-->0x21;
3. reg 0x11-->0x10;
4. reg 0x56-->0x1;
5. reg 0x1-->0x0;

Thanks a lot for help!

BR,

Elec Cheng