High CXPACKET and LATCH_EX waits
CXPACKET can be accompanied with a LATCH_XX (possibly with PAGEIOLATCH_XX or SOS_SCHEDULER_YIELD as well). If this is the case (and I believe it is, based on the question) then the MAXDOP value should be lowered to fit your hardware.

Besides this, here are some more recommended steps in diagnosing the cause of high CXPACKET wait stats values (before changing something on SQL Server):


Do not set MAXDOP to 1, as this is never the solution
Investigate the query and CXPACKET history to understand and determine whether it is something that occurred just once or twice, as it could be just the exception in the system that is normally working correctly
Check the indexes and statistics on tables used by the query and make sure they are up to date
Check the Cost Threshold for Parallelism (CTFP) and make sure that the value used is appropriate for your system
Check whether the CXPACKET is accompanied with a LCK_M_XX (usually accompanied with IO_COMPLETION and ASYNC_IO_COMPLETION). If this is the case, then parallelism is not the bottleneck. Troubleshoot those wait stats to find the root cause of the problem and solution


If you really need to understand the CXPACKET wait type in depth, I would advise reading the Troubleshooting the CXPACKET wait type in SQL Server article