Lately, when attempting to make the odd call, the call fails...and a pop up appears that says "Congestion". I've never seen anything like that before, and it only happens occassionally...what is that, and why is that?
it means that cellular networks, even as advanced as they are, are still limited. they can only handle so much radio traffic before they wont let any other calls go through.
network towers only have 8-12 channels depending on the area and population of the area, as far as i know. 2 channels for data. 1 for data and voice (if voice is needed it kicks the data for a short time). 1 for sms. so when those channels are full and the signal is to low btween your phone and the closest available tower, the call won't go through due to congestion.
It's just a symptom of being on the network "with the least dropped calls". I guess you can't drop a call if it never initiates it to begin with.
This and "call failed" happen to me often, as I am in a rural area.
Thanks AT&T!
I started a thread about this several weeks ago and barely got any responses. After weeks dealing with tech support, they finally admitted what I had been saying for weeks. I live in an upper middle class suburb of Dallas where EVERYONE has an iPhone. The tower that I connect to at home is completely bogged down and I can't make a call while on 3G. ATT has issued me 2 credits and said the issue will continue for "awhile".
Posted from my CrackBerry at wapforums.crackberry.com
When that happens I usually force it to 2G, seems to solve it.
As Xpimp stated you can force it to 2G (EDGE) IF your phone is unlocked. Although on ATT it's set up to auto switch, it takes some extrodinary circumstances. I can't post links yet, but just type in below to SEARCH and you will find all the info you need
How to: Disable 3G or 2G on AT&T Bolds without debranding
