Ironically, the carriers who have the most billing and call quality troubles are not the legacy incumbent local exchange carriers, its the newer VoIP based carr

Ironically, the carriers who have the most billing and call quality troubles are not the legacy incumbent local exchange carriers, its the newer VoIP based carriers. In your 10mbps scenario its either a lack of QoS on your circuit (either from you or your ISP) or poor generally qualities of the end to end connection - like too much jitter or something.