Bluetooth startup failure

Community General Discussions
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I'm building a robot using a Rasperry Pi coupled with a Picaxe board for motor controls. I realize maybe Arduino might have been the best option to start now, though I need an actual operating system on it.

I've been running into a problem: The Raspi has a 1A input limit for it's standard input. I've been feeding it 2A more through a GPIO voltage pin, and transferring electric to the Picaxe from another pin. I have a Bluetooth and a WiFi dongle plugged into the Raspi, along with a PiFace module, and eventually a USB controller.

The music would stop playing through Bluetooth after a few seconds due to a system hang. Amp or Volt drop, I'm not sure of, because the power supply has protection that shuts it off when I try to test. Thinking the PCB tracks might be too thin to carry 3.1A, I connected a powered USB hub to it (up to 3A, I connected 2.1), though it seems too slow to send WiFi AND Bluetooth data at the same time, so I keep the BT plugged directly into the Raspi. The music will sometimes play, but sometimes Linux will SHOW it's sending/receiving Bluetooth data, though it's not outputting sound. Music played directly from the Raspi still plays normal, so the sound chip is getting enough juice. 

Past couple times, after installing the powered hub it started the music fine. But then when I power it off and back on, it will do the above. I'm thinking it might be the powered hub sending power back to the Raspi, where it never completely "shuts of". I know powering it through it's USB jack IS possible, as I've done it as an attempted bypass: But it limits current, obviously.
The problem still happens even with the Picaxe disconnected and speakers powered by another source.

Can anyone find any flaws in my reasoning, or where to circumvent any of this, as I'm still noob-ish when it comes to circuitboards, amps, etc. 

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I’m curious, Reidmere, why
I’m curious, Reidmere, why do you think you need an OS for the Arduino?

The Arduino is a microcontroller and is designed to have one program (sketch) uploaded at a time. The Arduino Uno only has 2k of RAM and anything an OS uses takes away from the program.

It’s possible to do this, but it’s probably better to do it as a library, so only the functions used will take up space.

If I was going to write an Arduino OS, I’d base it around a forth system which would make the OS more compact and also easier to create. That might be a fun project…

Good building!

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Turns out I think I got it

Turns out I think I got it running. I swapped the Bluetooth to the powered Hub, and put the WiFi dongle directly into the Pi. This stopped the power on the Pi from jumping, as it’s consistant, compared to the BT that jumps depending on many factors.

I also changed the battery pack I was powering the hub from, I think it was pulling more than 5v from the hub that was connected, causing more fluctuations still. Thanks for all the input, nonetheless, I always enjoy opinions and information! I’m self-taught, so I still sometimes miss some foundations, so to speak.