Blotchy finish on American Beech

:C I have a serious problem with a blotchy finish on an American Beech sideboard I have spent most of the year making. I followed a process I have successfully used on oak: That is -
1. Sanded to 800 grit
2. Dilute shellac applied with cloth
3. Wiped off with 400 wet-dry sandpaper and white spirit
4. Organoil Danish oil applied liberally and rubbed in with grey scourer and wiped off with clean cloth within half hour.

Alas I've ended up with a very blotchy finish where some sections are darker than others and it's very patchy and terribly disappointing.

Does anyone know (1) how to rectify this; and (2) how I could then approach applying a finish which would produce an even lovely lustre?

Thanks a lot.