The biggest problem with the internet, hehe, is the fact that whatever traffic you send over it is sent in various paths at the same time, that finally meet up at the intended destination over a period of time(milliseconds). These paths are determined by the routers your traffic meets on its journey...but we will not go into the technology behind routers in this post

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This means what your downloading can be bouncing off many different networks (routers) that could even be half way around the world depending on your location and if the routing is that bad, however this usually isn't the case on good days

. Also, whoever is running the newsgroup should have redundant servers that help each other out during times of heavy usage. If not, then this could be where the problem is or it could be that their line is saturated with users.
Try running a tracert to the newsgroup. Open up the command prompt and type in
Code:
tracert www.somenewsgroup.com
while replacing the domain name with the actual newsgroup. This will echo out all the hops that the traffic passes by until it reaches its destination while reporting back times of how long the traffic took to pass that network. Look for very long times compared with the other hops. Now if the newsgroup servers are actually not part of that domain, then you will need to run a tracert to the IP address of those servers or if they have some sort of alias that is binded to that resolved IP. This is not guaranteed to work because in-between firewalls might block the ICMP packets, so just if you see it timeout...that is the problem.
Or their servers could be having some emotional issues...it happens

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