Speech Recognition stops working after a minute of nonuse

Question

I'm a grad student trying to keep from exacerbating my carpal tunnel and just figured out how to use the voice commands on my macbook. So far, they work great, they hear my voice, it does what I tell it to do, and I'm not constantly hitting apple+tab and apple+c and apple+v and so on, which really helps my wrists!
BUT. If I go for more than a minute or two without using a voice command, it stops working. I can't pinpoint anything else that triggers it other than if I stop using it for a little bit while I'm reading a paper or something. The microphone is calibrated and working, the little black arrows and the blue and green bars flash on the widget like it hears me, but then it won't give me the sound that says the command was recognized and it doesn't perform the command any time I try to use it again after a few minutes of not being used. It's like the recognition part goes to sleep and won't wake up.
If I go to the system preferences and toggle Speakable Itemst off and then on again, it starts working again until another minute or two of non-use. If I use spoken commands constantly, it will stay on for a good long while, but I'm not using it constantly that's the end of speech recognition. I really can't stop to just tell it some unneeded command to keep it awake all the time! Eventually, the computer gets confused if I turn the "speakable items" on and off too many times from the System Preferences, and it gets confused about whether or not it's turned on or off, or the widget disappears but the System Preferences panel thinks the Speakable Items is on.
I read somewhere that other people with a newer OS have a similar problem if they don't use the default speaking voice, so I switched to Alex and restarted, and the same thing is still happening.
I'm running 10.5.8, and using safari, word 2011, preview, nothing too crazy. My speech recognition is in "Listen only while key is pressed" mode, and like I said, works great until I stop using it for a minute or so. I'm using the internal microphone on my MacBook (dob circa 2008). Any tips on how I can actually keep my Speech Recognition useful? Thanks in advance!

Answer 1

OK, I have one more question now, seems to be the same as this question which was never answered years ago:
Speakable Commands>Application Switching -- how to delete items?
When I click on the triangle from the speech command widget and open speech commands, there is a TON of stuff there that I'll never ever use, but these things do not appear in the Library/Speech/Speakable Items folder so that I might be able to delete them. For example, one item I'd like to turn off is just the word "Home" and the computer keeps thinking that I said "Home" instead of whatever else I meant to say. Another keeps opening iChat or Mail, when I say "open new window" or something like that. I tried clicking, control clicking, option clicking, nothing will highlight a command in the Speech Commands window so that I might delete it.
The "Home" command only shows up when I'm using Word, in the "front window" list. However, the Application Speakable Items/Microsoft Word folder is empty. Is there some other way to get into the speakable commands list and weed out unwanted stuff?