Prime app closed caption progressively lags display

Prime app when showing captions start out in sync with the video but drift later in proportion to elapsed time so that after about an hour the captions are displaying about two to three seconds after the video frames they refer to. Good if you are learning a new language - not so good for people like me who prefer to listen to the original sound track, but still want to know what is going on.

Anyone else seen this? Any fixes? Might happen in other apps as well?