Does anyone else hear a high pitch whistle when starting off? It only occurs when starting from a complete standstill and lasts about a second (longer and louder if taking a while to get moving, eg. up a hill etc). The sound distinctively turns on and off and can be clearly heard outside the car (and faintly inside the car). I suspect that it is the inverter. But I'm concerned because a sound like this in electronics (eg TV, computer monitor) usually means a dying capacitor. Toyota dealer (at first service) didn't give it much thought. Should I bring it up again?
High-pitched and grinding noise? I have that when I power up the car. I think you are referring to the Prius reloading coolant which was stored (with other noises) in a "thermos" type device when you powered down. If by "starting off" you mean from a green traffic signal, then no, I don't experience that. The symptom of "longer and louder when taking a while to get moving" is probably something you should explain to a mechanic (again - I missed it the first time I read your post).
That would definately be the inverter. You'll hear it sing during regenerative braking as well. Most likely the caps singing - both of my Prius do it, I've considered it normal, and the only thing other than the motor whirs and tire noise that keeps this car from being truly silent in EV or Stealth modes.
You shouldn't be. Be thankful instead. You've got good ears. There is always a sound coming from electronic devices. Only, most of the time it is a such a high frequency that the average human ear can't detect it. It does come into range when the device is dying. But that's not what you are hearing. Prius simply operates at the lower range in the first place. Just ask others if they can hear it too. Odds are, you find quite a few that can't.
you must have good ears... i dont hear any of what you guys are describing... i do hear the regen but i cant call it a high pitched whine... but then again, maybe it is and i only hear the lower pitches...