The reason your internet becomes slower when you call to other states/countries is because your VoIP is using a lot of bandwidth that is shared with your internet.
I would contact a Vonage customer service representative with your inquiry. Your issue can be due to a number of reasons.. and I doubt anyone on this forum will be able to address all the possibilitie ...
1 Unlimited calling and other services for all residential plans are based on normal residential use by single-family household members. A combination of factors are used to determine abnormal use, including but not limited to: the number of unique numbers called, international calls forwarded, minutes used and other factors. Subject to our Reasonable Use Policy and Terms of Service.
HIGH SPEED INTERNET REQUIRED. † LIMITED TIME OFFER, VALID FOR NEW LINES ONLY. RATES EXCLUDE INTERNET SERVICE, SURCHARGES, FEES AND TAXES. As a subscriber to Vonage service, you agree to be bound by the Terms of Service. See www.vonage.com/tos for details. ¤ Where available. The number transfer process takes approximately 10 business days from the time you confirm your transfer request. Alarms, TTY and other systems may not be compatible. Vonage 911 service operates differently than traditional 911. See www.vonage.com/911 for details.
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