Newbie needs help

[Welsheeyore]

Hi. Just bought my first mr2.  It has come with a sub woofer and an amp behind drivers seat in the cubby.  Knowing that's what they are is the extent of my knowledge!  s:D s:D  

It has also been fitted with an after market - and I think this is called a double DIN?  s:?: :?: s:?:    s:?: :?: s:?:   I've done a load of research and I think this is the navigation unit from a 2008  s:?: :?: s:?:  highlander.

I've managed to connect my iPhone to Bluetooth.  
I've found online manuals to download for the navigation system

That's all I've managed

What I haven't managed/need help with is;

The sound is dreadful, and I can't find any way to adjust treble etc
The aerial isn't going up in ignition and making no noises
There is no radio
I can't find a CD player   s:D s:D  

Having watched YouTube I'm not keen on having to undo everything to get the head unit out to see if the aerial is plugged in   s:shock: :shock: s:shock:  

But I suspect that's the next step - I think the aerial fuse works other items from what I've read on here, what else wouldn't work if the fuse was gone?

I really hope someone can help me, what I would ideally love is the previous owner to be on here and read it   s:lol: :lol: s:lol:    s:lol: :lol: s:lol:

[Ardent]

Hello and welcome.
Post a pic up. May help to identify it.