Aug 5 (Reuters) - TASER-maker Axon Enterprise posted lower second-quarter gross margin on Wednesday, weighed ‌by a higher mix of less lucrative ‌professional services and investments in scaling new product offerings. • Under the professional services business, the company supports implementation, configuration and ongoing workflow integration. • The software-only segment's gross margin exceeded 80%. • The company's gross margin fell 40 basis points to ‌62.9%. The impact on quarterly ​gross margin was partly offset ​by strong performance ​in the connected devices segment.