Catalina

Hi I am using DSM 6.2.3-25426 update2 with jun's 1.04b bootloader and ig-88's 0.13.3 extra/extra2 lzma driver. and my mainboard is an asrock H110m-itx/ac. but there is weird thing. File upload speed to nas is full wire speed (1gbps), but download from nas is stuck at 80MBytes/s (700Mbps) Although I change many network setting on DSM control panel, but it is not changed. Finally, changing to jun's original lzma driver, I can download with full wire speed from nas. but due to hw transcoding, I can't use jun's original driver. Is there any solution or experience for it? Thank you in advance.