R15b5 : EDIT TAB : Blade Tool VANISHED

I have not worked out the exact scenario to consistently repeat this issue:
+) When listening to an AUDIO track in the EDIT tab for 20 mins / using J/K/L to add markers .. the BLADE tool vanished.
+) A -> B -> A -> B ... did not get the Blade tool back
+) EDIT TAB -> COLOR TAB -> EDIT TAB did not get the blade tool back.
Clicking on the AUDIO Did cause a Blade cut in the Track .... and the BLADE at cursor reappears.
AJ
+) When listening to an AUDIO track in the EDIT tab for 20 mins / using J/K/L to add markers .. the BLADE tool vanished.
+) A -> B -> A -> B ... did not get the Blade tool back
+) EDIT TAB -> COLOR TAB -> EDIT TAB did not get the blade tool back.
Clicking on the AUDIO Did cause a Blade cut in the Track .... and the BLADE at cursor reappears.
AJ