Q: Apple Wireless Keyboard "haywire" typing

After I leave my desktop for a period of time, when I return and start typing a variety of problems arise.  The letter do not appear, at times a small window with letter accents appears, at other times a few strokes will produce a series of letters (usually when I am logging  into something).  When I turn off the keyboard and turn it back on these problems disappear and things work as they should.   Yet, when I leave my system and keyboard on after I wake it from sleep these typing problems return.  I do not have any connection bluetooth connection problems.  All my Apple bluetooth devices stay connected.  Is there a solution or is this the beginning of the end for my keyboard?