Flush disk. This is very common and I don't consider it as a fault. You can increase pressure using fine grinding settings or overfilling basket slightly. Other baskets show correct pressure when in use.
Sage Barista Express Impress Coffee Machine Bean to Cup Black Stainless Steel
SAGE Barista Express Impress Coffee Machine Stainless Steel SES876
SAGE Barista Express Impress Coffee Machine SES876BTR Bean to Cup
