Hi,
If you are using dv footage use dv preset when you open an poject or avi project otherwise. While exporting check under settings, what compressor you are using “none” is best to maintain quality.
But your system should be capable enough to playback an uncompressed avi file.
If working with dv, you can easily export back to “microsoft dv avi” and compressor as dv PAL/Ntsc as the case may be. not dv24 unless your source is dv 24.
ps: keep lower field first for dv sources
Sameer Shrivastava