Accessory Not Supported

[sargentsam]

I got a brand new InStudio wooden dock for my iPhone 4s for Christmas.
I placed my iPhone on the dock and it immediately started charging. But I got a notification saying "This accessory isn't supported by this device".
When I try to play music through the speaker dock, it doesn't work.
I also tried my moms speaker dock from Sony that worked with my iPod 4. It doesn't work?!
Can somebody help me?

 

[Newtons Apple]

Sounds like the InStudio wooden dock is not comparable with your iPhone.

 

[sargentsam]

But what about the Sony dock?
It says ON THE BOX that it is designed for iPhone 4s.
And the Sony one worked with my iPhone and I gave it to my mom. Three months later it doesn't work with my iPhone?!
Is it due to iOS 8 or something?

 

[tiartrop]

You might want to try out cleaning your charging port first, check if it's dusty.

 

[sargentsam]

I have cleaned the port.
I cleaned it a while ago. My phone works in my surround sound system. I place it in the dock cradle and it works for that one. But it doesn't work with these two.
I don't understand. It used to work fine but now it doesn't.