Twitter is not working correctly on my home internet?

[Dallas]

About a month ago out of no where my twitter started acting very slow on my IPhone (4s, newest software update) and I could not load/view a single picture. This includes profile pictures and pictures tweeted by other users. I can refresh my feed with no problem, but all the pictures show up as grey boxes and when I tap them to open them, the loading bar doesn't even budge. The moment I turn my WiFi off and use 3g Twitter works perfectly. This problem is also happening to all IPhones using my WiFi, not just mine.

I did not update/change anything to cause this problem. Before this problem I never had any WiFi or internet problems. Everything else is working fine over WiFi. For instance: Instagram pictures, Facebook pictures, and snap chat all work perfectly.

About a week ago I decided to log into Twitter on my PC (hard wired into router) for the first time. The same thing happens where I cannot view a single picture even if I try open open them directly by clicking of the link.

I am wondering if there is a port I need to open on my router to get this to work. Also I should add that there are no firmware updates for my router. I am using a Comtrend ADSL Bonded router.

Things already tried/Don't tell me to try:
-Reset router (multiple times)
-Update router firmware/software
-Delete and re install the Twitter app
-Make a new twitter account

Thank you in advance for reading this. I know it is very long, I just didn't want to leave out any facts.
Twitter does use an https address. But many other websites I use do too and they all work fine.

[Thomas]

I commend you for the detail contained in your question. All of it is necessary.

Is it only twitter?
Does your twitter use an https address?
Can you see images on other https web sites?
( if not you have now narrowed it down to https addresses)

As an experiment can you set your phone up as a wifi hotspot, get your computer to access it then go to twitter, and see if twitter displays its images.

I know that none of these will solve your problem but they may help to narrow down what is causing it.