Proxy settings in browser

By the way, this is my first time managing a server, so pardon me if the question I ask seems stupid.

My site is having problem displaying some of its content. Sometimes, it will be images missing, css, or a certain page. Never had this problem when I was doing development locally. I solved this by setting my proxy settings in my browser, but I can't expect everyone using the same ISP here to do the same.

I determined this issue has to do with my local ISP since I had to manually set the proxy settings to 1 that was recommending by the ISP.

What do you think is the problem here? Should I contact my ISP? Or is it my configuration for my apache server that is preventing access?

ps. I'm from Singapore, ISP is Singnet, Proxy that I used to solve the problem, proxy.singnet.com.sg 8080, linode ip 74.207.248.185, site www.nobstudio.com

TIA