RAX120 randomly resets my CM 1000 modem?

Hello all! Not super knowledgeable about tech and the like. I recently purchased the RAX120 as an upgrade from my R8000P. Since having this new router, my modem randomly reboots. I tried a couple different things (including contacting ISP, resets on all devices, trying multiple connection variations between devices, etc.) before coming to the conclusion that when the RAX120 router is connected to the CM1000 modem, the CM1000 will completely reboot very often (especially when using streaming services). This does not happen when the R8000P and CM1000 are connected. I haven't altered a lot of the default settings on the RAX120 and it is running firmware version V1.0.1.136. I haven't been able to find any information specifically addressing this or whether the RAX120 and CM1000 are incompatible. Is this a known issue, is there a solution, or will someone be kind enough to help me out with this?