I have a similar problem with packet loss on orange pi rk3399 when connected on 1Gbps/Full
Armbianmonitor: http://ix.io/4ia5
[ 10.377653] rk_gmac-dwmac fe300000.ethernet eth0: PHY [stmmac-0:01] driver [RTL8211E Gigabit Ethernet] (irq=84)
[ 10.386477] rk_gmac-dwmac fe300000.ethernet eth0: Register MEM_TYPE_PAGE_POOL RxQ-0
[ 10.396512] rk_gmac-dwmac fe300000.ethernet eth0: No Safety Features support found
[ 10.396545] rk_gmac-dwmac fe300000.ethernet eth0: PTP not supported by HW
[ 10.397193] rk_gmac-dwmac fe300000.ethernet eth0: configuring for phy/rgmii link mode
[ 10.557743] aufs 5.15.41-20220620
[ 11.825681] bridge: filtering via arp/ip/ip6tables is no longer available by default. Update your scripts to load br_netfilter if you need this.
[ 11.831210] Bridge firewalling registered
[ 12.194629] Initializing XFRM netlink socket
[ 12.666036] rk_gmac-dwmac fe300000.ethernet eth0: Link is Up - 1Gbps/Full - flow control rx/tx
[ 12.666114] IPv6: ADDRCONF(NETDEV_CHANGE): eth0: link becomes ready
root@orangepi-rk3399:~# speedtest
Speedtest by Ookla
Server: DOM.RU - Yekaterinburg (id: 5844)
ISP: Dom.ru
Idle Latency: 2.01 ms (jitter: 0.09ms, low: 1.96ms, high: 2.13ms)
Download: 629.96 Mbps (data used: 888.3 MB)
66.92 ms (jitter: 50.00ms, low: 1.11ms, high: 875.41ms)
Upload: 1.36 Mbps (data used: 2.5 MB)
1.58 ms (jitter: 5.65ms, low: 1.22ms, high: 210.62ms)
Packet Loss: 8.3%
Result URL: https://www.speedtest.net/result/c/70477fc4-89f0-4b2a-b9a7-4248e25af9d7
After switching to 100 Mbps packet loss disappears:
ethtool -s eth0 autoneg on speed 100 duplex full
[ 614.706367] rk_gmac-dwmac fe300000.ethernet eth0: Link is Down
[ 616.829581] rk_gmac-dwmac fe300000.ethernet eth0: Link is Up - 100Mbps/Full - flow control rx/tx
root@orangepi-rk3399:~# speedtest
Speedtest by Ookla
Server: DOM.RU - Yekaterinburg (id: 5844)
ISP: Dom.ru
Idle Latency: 2.03 ms (jitter: 0.12ms, low: 1.86ms, high: 2.15ms)
Download: 93.89 Mbps (data used: 42.3 MB)
2.90 ms (jitter: 0.32ms, low: 2.03ms, high: 4.10ms)
Upload: 93.80 Mbps (data used: 43.5 MB)
3.89 ms (jitter: 0.60ms, low: 2.46ms, high: 8.08ms)
Packet Loss: 0.0%
Result URL: https://www.speedtest.net/result/c/03847e3f-6400-457f-bd6b-067b59b9c243