Auto-masking + Large # of Channel imaging gets stuck

Hi,

I'm trying to you auto-masking + thresholding to multi-channel clean a point source close to the phase center of my image. Here is my full script,

wsclean -size 2160 2160 -scale 0.05arcsec -pol I -auto-mask 3 -auto-threshold 0.3 -mgain 0.85 -niter 1000000 -channels-out 128 -fit-spectral-pol 3 -join-channels -verbose -name test -fits-mask test.mask -data-column DATA -no-update-model-required -weight natural -no-mf-weighting test.ms

I've narrowed it down to it constantly freezing at this point, where I assume i has identified thousands of components below the threshold.

I'm not exactly sure how this is possible because I'm also including a manual deconvolution mask that's only ~2x the FWHM of the synthesized beam centered on the bright source. Furthermore, this exact script words fine if I just go from 128 to 64 channels at finishes running in ~5 minutes, I've left the 128 channel version running all night but it is just stuck at that pint. Maybe this is key information, but 128 out-put channels corresponds to 8MHz incremental imaging, and I have a fair number (~10ish out of 128) of consecutive 8MHz sub-bands flagged, so maybe the flagging is causing an issue, and this is a bug? Let me know if you need anything else or my ms-file/manual mask.

Cheers, Andrew