my kiln wash problem

[slats]

I have applied be wash to my shelf before with no problem. This time when I applied it I noticed it was an orangy color rather than the pinkish that it was at earlier applications. I had just mixed an new batch. Okay, fired it before using and looked fine until I fused a piece (2 layer plus design)....Got a big bubble........Then tried a raking( usual setup) got about 6 bubbles.....Whats going on here? The shelf is level etc. Could the kiln wash be bad? Why would the color be different. It also seems to come off very easily - sticking onto pieces. Help