Analysis board sometimes stops working after 'previous move' button

When using the analysis board, after pressing the 'previous move' or 'current move' buttons, sometimes I cannot make any more moves without closing the window and opening another copy.

In addition, in the regular coorespondence game window, after making a move and then clicking 'previous move' or clicking elsewhere on the board to try a different move before pressing 'Submit', sometimes the board will not let me make any more moves without refreshing the page.

This seems to happen only in this unrated 960 game I'm playing against my brother: http://www.chess.com/echess/game.html?id=43267075# and not in any other games, so hopefully this is an isolated issue.

Investigating this for you.

I have exactly the same issue in the 960 game I'm playing. The Analysis window doesn't work on my MacBook in my 960 game yet seems to work fine in all my normal games.