hmm...
My opinion of why there was arkward silences is because of lack of experiance and confidence.
If you were to talk on the phone to gilrs on a regualr basis u would be able to keep the conversation alive and interesting for ALOT longer than just 6-8 minutes.
I said confidence because you were probably a little shy on the phone too.
When i 1st started totalk to girls on the phone alot etc, i went through the same thing, i neva knew what to say, i neva knew HOW to say things etc.... But after doing it often, i found myself able to hold a nice enjoyable and entertaining conversation with a girl for hours.
Now the only problem that i MIGHT have is not having anything to talk about with a gilr cause i have talked about everything there SI to talk about with her. ( not that i DO actually ruin out of things to say, there are always things to say)
A way to help u avoid that arkward silence is to just think that its one of ur best buddies on the other line. ( I'm sure u dont get any arkward silences with ur buddies on the phone, now do u?)
Ok, well i hope this helps u in the future.
Laterz..