It sounds like you are experiencing problems with Acetaldehyde. Most people associate this with a grassy or green leaf flavors. Lighter Ales don't mask flavors well therefore they will be more noticeable or pronounced.
I move the beer to the secondary which is usually after about a week.
I doubt it's the trub! Most likely you are transferring off the yeast cake to soon, or its bacteria. It is not going to hurt anything to wait a few extra days or a week after the beer reaches its FG especially on lighter beers.
The Yeast is still active after the primary fermentation cleaning up after itself, Even though the beer has finished out. Lighter beers take more time to Condition.
You could however have a bacteria infection. Does the beer have a sour note? If so it could point to a Lactic Acid Bacteria.
Either way, Cold conditioning for an extended time should mellow out the off flavors.
Cheers
Preston