OpenCL problem with nvidia driver

Can you get help here with OpenCL problem related to nvidia HW and driver?

on a GeForce RTX 2080 Ti i run a custom OpenCL application. It runs for several minutes. All allocations are done at startup and subsequent memory accesses are only done by clEnqueReadBuffer/write buffers for existing buffers.

It runs fine for minutes. It has about 4 GByte allocated on GPU. Same kernel all the time and all of a sudden the OpenCL api reports CL_OUT_OF_RESOURCES

Plenty of memory left. Depending on driver i get this error sooner or later.

The same sw runs on other HW such as 1060 with 6 GByte mem.

How can i find this problem and why does this only occur on one machine ?