A:AnswerTo answer your question Ran,
1. No, you will not be able to control the speaker volume independent of each speaker.
2. You can plug all the 5, or the front 3, or just the center. Sub-woofer is optional.
A:AnswerI am not a apple person but I see no reason why it should not hook up to apple since it only needs Bluetooth or NFC and will connect up. It works great with my Samsung galaxy 4.
A:AnswerHi Tony, please refer to pg.20 of the link below for more information about connecting other types of equipment. I hope it helps. Regards, ^Ron
https://docs.sony.com/release//BDV-E6100_E4100_E3100_E2100.pdf