With the new 188.8.131.52 level of SSDR and firmware, I find the problem where pressing the power off button does not result in a shutdown for about a minute still remains. I know this was written up before, but I can't find it at the moment. One thing remains true with this problem - if you have transmitted since powering on, then it powers off correctly. If you have not transmitted, it hangs in the process, leaving the FLEX-6500 in the annunciator lights. At this point, if you momentarily depress the mic PTT switch, it will immediately start the shutdown process. I have not tried pressing the key to see if that also does it. Hope something here is useful.