As I found (and hence why i gave up on the wiki) is that different firmware's do different things even in the same gen - although i wasn't aware this issue has trickled back down to Gen 1, so I assume you have the newer fast response firmware for this to be an issue (my two are too old and well go BANG on that firmware)
I think they've removed the ability to see the actual register being sent from the portal & I'm currently having this exact same discussion on FB so this is copy paste but:
So I'm trying to do this without getting too technical/splitting hairs (ultimately you can't fully "pause" by setting discharge rates to 0 because you can't actually set 0.)
When you change the power slider in the app/portal this is translated numerous times from a value you desire, to one the inverter can actually deliver. (You can via the API set power as a %age value or a Watts value to further confuse things)
Ultimately Givenergy chose an obtuse way to scale power in the inverter such that you have:
The battery capacity (in AH x 0.5) x 51.2V.
The power registers in the inverter are actually scaled 0-50 rather than 0-100, so divide that value /50 gets you your minimum power steps value.
So for a 9.5kWh battery you minimum steps in power are 95W.
8.2kWH packs are 82W (you get the idea)
More than one battery? Well your steps get added together so that becomes your minimum value....
For "reasons" the newer gen stuff seems to struggle with anything less than the first 3 steps so the minimum it'll go to is 285W which given measuring is a bit finger in the air sounds about right yours showing 300W.
I know this is pedantic but unfortunately it's just how it all works.
so @DD I'm not sure if this helps or hinders but that might be a few things to try - incremental steps on the low end in both directions to see what it does