Lower hashrate at pool and miner

[murgorx]

Hello guys,

recently I started a small 4x3080s mining rig and have been monitoring the performance of both my rigs.
Previously I was mining with a 5x RX580 and the pool used to show almost always a constant speeds. The reported hashrate at the miner was 151 mh and the AVG speed used to be the same.

Since this week, as I added the 2nd rig to the equasion, I seem to have somehow lower hashrate than reported.

@ the pool, Ethermine, now I am getting a median speed of 510 MH, when the reported is 530.
https://imgur.com/a/WhIBleR

I have left the 2nd rig run for more than 24 hours to see if it's stable, but the hashrate seems to be really off.

Could anyone explain to me why my hashrate is about 70% of the time below the reported hashrate and by that many mh/s. Is it caused by the enourmous global hashrate currently or is the issue due to some wrong configuration?

[FP91G]

What is Reported Hashrate?
Reported Hashrate is used by mining software to determine the submitted computed hashrate of the hardware to the pool. The reported hashrate is essentially used for comparing it to your calculated hashrate shown by the pool. Reported hashrate is generally inaccurate and that's why there's always a small difference when comparing it to the calculated hashrate. It is a value only displayed by your workers' mining software.

What is Mean or Calculated Hashrate?
Mean or Calculated hashrate is calculated from the accepted hashes that your hardware has submitted to the pool. This value can fluctuate above or below your reported hashrate. The rate is impacted by such things as stale shares, invalid shares, changing hash difficulty and pool's luck. Your worker may submit more or less shares during a given period of time that are accepted by the pool.

What is Average Hashrate?
Average is exactly what it's called – an average. This is the average effective hashrate over a specified period of time. The higher the better.

source
https://hiveos.farm/hiveon-pool-general_pool_faq-general_faq/