Hello Remah, I'm sorry, I certainly understand your frustration. Other VoIP services such as Magic Jack usually work fine with Exede, your calls however may count toward your data allowance where as Exede Voip calls are not counted towards your data usage.
I have been pleasantly surprised with my Magic Jack experience. I knew I was taking a chance after seeing several negative reviews. But I also saw some good reviews and signed up. I notice almost no latency and the data usage is negligible. The best part - my bill went from $35 per month to $35 per year.