Are there any known reasons Grafana intermittently fails with an EOF error when querying Druid with increasing frequency as it approaches real time

[RichardChester]

I am using the Druid data source for Grafana and have a query that runs every 5 seconds to retrieve and display data. The plugin seems to work fine when querying over a huge amount of historic data but will fail with increasing frequency as I query data closer to 'now' even though the total data I'm requesting is far smaller than the amount it is capable of. The error is

Unexpected EOF

I have checked the query and it is valid and I've queried the same data with the same query 10 minutes later and it worked. Can any one think of a reason why this might be happening ?

Thanks in advance

[jbguerraz]

Hm, I have no real clue, but if you copy/paste that query into druid console or any other client, does it works instantly fine ? or do you have to wait 10 minutes or so as well before it works properly ? just to discard or not the grafadruid side of it.