iPod Touch will charge but won't play when connected to a Sony docking system
Solution 1:
I found a product description on the Best Buy website:
The ICF-CS15IP is Compatible with most iPod® and iPhone® models, including iPhone 4. Works with: iPod touch® 2nd, 3rd, & 4th generations, iPod nano® 3rd (video), 4th (video), 5th (video camera), & 6th generations, iPod classic®, iPhone® 4, iPhone 3GS, and iPhone 3G.
Your 4th generation iPod Touch is listed as supported by this device, so you should contact Sony and expect them to help you.
Solution 2:
Just bought the sony ipod docking station for my daughter for Christmas. Her IPOD Touch 4th generation will charge, but the music will not come out of the docking speakers. My son has an older IPOD Touch and it worked fine. I called Sony and they told me I had to reinstall the operating system on the IPOD touch 4th generation for it to work. I went through the hassel of resetting back to factory settings. Still did not work.