Core Viewpoint - Nubia Z70 Ultra is facing a significant quality control and trust crisis due to hardware issues and ineffective after-sales service, leading to a surge in user complaints [1][8]. Group 1: Quality Control Issues - Users reported that the Nubia Z70 Ultra speaker produced harsh sounds just one week after purchase, raising concerns about manufacturing quality and reliability [2]. - Complaints include screen burn-in, excessive heating, and rapid battery drain, indicating systemic quality issues [3][4]. Group 2: After-Sales Service Challenges - The "180 days exchange only" policy has been criticized for failing to provide effective solutions, with users experiencing unhelpful responses from customer service [3]. - Specific cases highlight that even after replacement, users continued to face similar issues, undermining confidence in the after-sales process [4]. Group 3: Historical Performance Issues - Previous models like Z60 Ultra and Z50s Pro also exhibited problems with system optimization and hardware stability, suggesting ongoing issues within the product line [5]. - Users reported multiple minor issues, including unresponsive touch screens and poor Wi-Fi connectivity, which persisted even after replacements [6][7]. Group 4: Brand Trust Crisis - The cumulative effect of quality control failures and inadequate after-sales support has led to a broader brand trust crisis for Nubia, particularly in the high-end market [8]. - The situation serves as a warning to other companies aiming for the high-end segment, emphasizing the need for stringent quality control, efficient after-sales service, and consistent system performance to build customer loyalty [8].