As wireless technologies continue to advance, high-order modulation schemes such as 1024-QAM have been introduced to significantly increase data rates.Compared to lower-order schemes, 1024-QAM is more sensitive to signal degradation, which may affect overall performance. Despite its growing use in Wi-Fi 6, there is limited research evaluating how physical-layer conditions impact retransmission rates when using this modulation scheme.The analysis focuses on three parameters: channel width, transmission distance, and transmit power. A hardware-based testbed was used to generate TCP traffic and collect retransmission data using Wireshark. Widening the channel from 20 MHz to 40 MHz increased packet volume to three times and left a decaying retransmission trend, while the 20 MHz pattern stayed flatter. Reducing transmit power from 100% to 25% did not affect the performance. Distance barely changed the retransmission rate out to 22 meters, but packet volume dropped sharply beyond 22 meters. We offer practical configuration guidance for network designers.