Volume keyframes deleting themselves

Hello,

I have build 11.0.1.49 of Audition CC, and am currently in the final stage of finishing off a 55-minute radio documentary.

Alarmingly, when having a listen through to a mixdown of the latest edit, I found that two pieces of music had had all the keyframes removed from them to fade them under speech. These keyframes had deleted themselves without any action from me.

Is this a known error? Is there a bug?

Many thanks.