intermittent upload problems

Hello all, i am rather new to the arduino community so please explain things to me.

I got my arduino duemilanove about a year ago and installed version 0018 of the software on my ubuntu box just fine. everything uploaded consistently with no issues. I put the arduino away for about 8 months and now that the semester is over i am back to playing with it.

Between then and now i have put a new install of ubuntu on my machine and lost the 0018 version install.

So I installed the newest 0021 yesterday from the website and things where uploading fine until i got an error message.

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding

I got this almost consistently. I tried to hold down the reset button trick and that works sometimes. I have a sketch uploaded with the TLC5940 library and led's hooked up to it. When i hit upload the lights turn off and the tx/rx lights blink but it doesn't respond about 80% of the time.

SO, i downloaded and installed the 0018 package and it seems to be a little more consistent. about 50% of the time i can get it to upload. but now i am getting 2 error messages intermittently.

I get the one listed above sometimes AND other times I get

avrdude: stk500_getsync(): not in sync: resp=0x26
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x26

I had installed avrdude from the repo's in ubuntu and read that this might be causing issues. so i purged it from my system, and am letting arduinoIDE use its version of avrdude.

so in recap. I cannot consistently upload and sometimes i get

avrdude: stk500_getsync(): not in sync: resp=0x26
avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x26

and other times i get

avrdude: stk500_recv(): programmer is not responding
avrdude: stk500_recv(): programmer is not responding

when i upload the LED's i have attached to the TLC5940 chips do turn off, and the tx/rx lights blink.(the boot loader light also blinks) but i get error messages 50% of the time.

Any help or suggestions would be great. THank you in advance

Also on an unrelated issue, when i have my cable hooked to my board and a program is running, if i move my cursor over the tools tab. the board stops the program, until i move it off of the tools tab…is this normal?

Cable issue

No that is not normal, but if your cursor is moving probably your mouse is too and I guess that the cable of the mouse touches and moves the cable to the Arduino or the USB connector on the inside of your laptop/PC and cause the failure indirectly. Think you need to replace cables and see if it still happens.

I've tried 2 cables. and am on a laptop using the touch pad. no external devices except the arduino. both issues persist.

OK, i used the directions here http://www.arduino.cc/playground/Linux/Ubuntu to install from the repos. The install told me i needed a java package, and now it seems to be running fine. No errors on upload, I cant find the name of the package that was installed but it was def a java package.