Blomberg dishwasher not filling properly or spraying water

Hi.

I’ve got a Blomberg GVN9483E integrated dishwasher that isn’t spraying water and only fills around half the water it should in the base. I’ve done the following in this order with these results:

1. Checked and removed all the filters and all were fine with no blockages.
2. With no water spraying, I assumed the water level was too low for the circulation pump to work properly, so I manually filled the base to the correct level, but still no spray, although the water heats up just fine. The circulation pump just makes a regular slow thudding noise and water slowly bubbles out of the end of the pipe if I remove the lower spray arm.
3. After checking the hoses to and from the circulation pump and finding they were all clear, I assumed the circulation pump must be blocked or not working properly. So I ordered a new one, fitted it, but still it won’t spray and I still get the slow thudding noise from the new circulation pump and again, water slowly bubbles out of the end of the pipe where the lower spray arm should go. So the circulation pump isn’t the fault.
4. I’ve had the side off and checked the matrix and it’s pretty clear. I took it off and gave it a shake with water inside to make sure and no change when refitted.
5. I’ve had a good look at the pressure chamber and clear pipes to/from it and it looks really clean from the outside, although I haven’t actually pulled it out of the machine.
6. I’ve run the dishwasher with the side panel off to see how quickly water is going into the matrix and pressure chamber at the start of the cycle and to my eye it seems slow. The matrix never gets much water in it, but it could be normal, I don’t know.
6. Thinking the slow filling could be indicating a low water pressure problem, I’ve checked the mains water pressure coming through the hose by disconnecting it from the back of the dishwasher and it seems fine.
7. Again, to rule out a possible water supply problem, I’ve fitted a brand new water inlet valve and still no change to the speed of water going through the matrix or amount of water going in the base of the machine. It still only fills the base with half the water it should and doesn’t spray even if I manually top up the water level in the base to the correct amount.

I’m a bit stuck now to know what is causing these problems. There are no error codes on the display to go on, so can anyone here suggest what I’m missing?

Many thanks!