I have noticed on S4 chassis equipped with I/O fabrics modules that transceiver leds are blinking with 2 different colours: most of them are green, but some are amber (see enclosed images - I hope it is visible).
Generally, all ethernet port status dual LED status as follow. left LED blinking means theres activity. left led: Amber means 100Mbps. left led: Green means its 1 Gbps or more. Right led: Green means port status is active.
If right led green is also blinking, means its very odd.