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Continue to ChatConfiguring your Grandstream telephone adapter for secure calls on VOIP.MS https://blog.oppedahl.com/configuring-your-grandstream-telephone-adapter-for-secure-calls-on-voip-ms/
Configuring your Grandstream telephone adapter for secure calls on VOIP.MS https://blog.oppedahl.com/configuring-your-grandstream-telephone-adapter-for-secure-calls-on-voip-ms/