My has started making a 1-2 sec squeal about 10-30 secs after I start moving having just started the car. Sometimes it doesn't make this sound. It sometimes makes the same noise as I shut off the engine. Is this the inverter coolant pump going out? It sorta sounds like a slipping belt but not nearly as loud or annoying.
This is probably the serpentine belt slipping on the air conditioner compressor pulley. Try turning the A/C button on and off to see whether you can force the noise to appear. If so, then you should have the belt replaced. The belt costs around $20 retail and is not hard to replace, maybe one hour of labor time or less. If you DIY, I suggest that you buy only the correct Toyota part.
Tried the AC thing, thats not it. Today it did in direclty after I put it in D (drive). Its not loud and I don't even notice it with the windows up and the radio on.