My ADP8101 after years of happy service started to make strange ‘groaning’ noise at the beging or end of the wash/dry cycle. It appears to be coming from the bottom of the machine usually as the machine is drying the load, but occasionaly when switched on. Opening the door halts the cycle but does not stop the strange noise. I had an overhaet problem about 6 months ago that was cured by re-setting the thermal trip with advice from this forum 😀
Drain pump, perhaps? It runs right at the start of the programme and is used during the drying sequence. Tired/worn pumps can make some interesting noises.