I've been having this noise for a while. It happens when the car is warm. I've looked through the forum and found people having a similar issue but on cold engines.

To me it sounds like tappets ticking under load between 1500-2000 rpm when slowly accelerating. So it's usually when going uphill, but it does rarely happen when going on a flat road. I can't hear it when accelerating at higher rpms or when the engine is cold.

I asked about it at the last service at Volvo and they said it's coming from the gearbox. The gearbox was serviced only 2k ago and the noise was present before that.

The noise follows the rpms, it's not a constant tick or traveling speed related.

Anyone has any ideas? I started noticing it after the service before last one and I noticed the dealer changed from Castrol Edge to Magnatec, both 5W 30 and A5 oils.