High miner rejection rate may be resulting from the following reasons:
1. Poor network and slow speed
Miner connects to mining pool. And mining pool regularly distributes jobs to miner, then miner submits shares to mining pool, which involves a large amount of data transmission. Network performance has a direct impact on hashrate and rejection rate of miner.
You can confirm network status by the following steps:
1) Connect your computer to the network where miner is connected
2) Open cmd command prompt on your computer
3) Enter ping + space + mining address of a certain currency in Poolin. For example, if I want to confirm the network performance of miner on Beijing ZEC node, I can enter ping zec-bj.ss.poolin.me And press enter to get the result.
Usually the ping value is a normal range within 50ms.
2. Miner temperature is too high
High temperature of miner will also affect hashrate and rejection rate, especially in hot summer. The temperature in the screenshot below is basically normal. Different miners have different rated temperature and it is usually normal for temperatures below 90-100. Please refer to rated temperature for different rigs.
3. Firmware issue
Some miners may generally have a high rejection rate due to firmware issue. If you encounter the situation, you may consult miner manufacturer.