I recently encountered a puzzling issue while updating my project from Nordic SDK 2.7.0 to 2.8.0. The problem revolves around the UART reception performance, which has significantly decreased. Specifically, devices without hardware flow control are occasionally losing data when operating at higher baud rates, such as 115200. This was not an issue prior to the update, and reducing the baud rate to 2400 temporarily resolves the problem but is not a practical solution for my application. After some research, I discovered that a new serial driver was introduced in NCS 2.8.0, which might be the root cause of this behavior. I’ve tried increasing buffer sizes and adjusting interrupt priorities, but these changes haven’t yielded any improvement. The ISR code I’m using is modeled after the ppp_uart_isr function in drivers/net/ppp.c, and it prioritizes RX over TX, yet the issue persists. I’m curious if others have experienced similar issues or if there’s a known workaround or configuration adjustment that can mitigate this problem. Additionally, I’d love to hear if anyone has successfully implemented a solution using the asynchronous API or DMA for UART operations, as this might be a viable alternative. If anyone has insights into the underlying cause of this performance degradation or suggestions for optimizing the current implementation, I’d be incredibly grateful. Your experiences and advice would be invaluable in resolving this issue and improving the reliability of my project. Thank you in advance for your time and assistance!