mix down has gaps, help!

[bbq2105]

I needed to transfer a 25 minute speech from cassette tape to CD, so I went out from the deck headphone jack into the line in of my M-audio USB interface.

Besides the poor quality that a cassette provides in and of itself, the original recording had an unbearable amount of hiss (think lapel mic in a church). There were also many long pauses that were tedious to listen to.

I cut out the pauses. Then I eliminated almost all of the hiss using Voxengo Redunoise VST. That Redunoise was amazing. Finally, I evened out some spots where the speaker laughed too loud, etc. Listening to it through the Mixcraft application it was flawless (no skipping, hiss, even levels, etc).

When I mix down, my final mix always has about 3-4 spots (different spots everytime) where the audio completely cuts out for 1/2 a second.

I have tried mixing down to mp3, and wav.
I have tried "save as" and choosing the best quality.
I have tried buring directly to CD

Every time, it has those 1/2 second gaps, and like I said, they are in different spots all of the time.

I am using a four year old Vaio laptop (I know it is still not a lot but it came with 512mb of RAM and I have since upgraded to 1024).

I tried shutting down any programs that look like memory hogs, but I have not tried shutting down every little program.

The Voxengo Redunoise VST is the only plugin I used. Should I experiment with mixing down with no plugin at all, just for kicks? (it is going to be noisy as heck)
Any ideas???

Thanks so much.

[Acoustica Eric]

Yes this definitely sounds like the plugin is going goofy at random spots. try mixing down without it.
You could use Spin It Again to record the cassette and remove the noise, that is exactly what the program was made for. You could then have SIA make a wav file of the recording, then import into Mixcraft for final editing.

[bbq2105]

Thanks Eric, I'll give that a shot.