This is a problem in the HM-3.1-dev-dqp branch.

When using EntropySliceMode 2, i.e. fixed number of bits (for VLC) or bins (for CABAC) per slice, CompressCU will sometimes produce CU:s too large to fit in a slice, resulting in slices larger than the specified limit. This could be avoided if the encoder made the decision to split the CU (unless the CU is already of slice granularity size or smaller). A split decision check is already implemented in xCheckBestMode for regular slices, but no similar check is performed for entropy slices.

The fix for this would be to add a similar check for entropy slices. Note that for this to work for CABAC where a bin threshold is used, code to keep track of the number of bins encoded during compression is needed too.