I also am not getting images from TIDAL, checked the ROCK NUC logs directory, found lots of these:
04/27 11:28:41 Warn: [broker/images] unexpected error GET'ing https://imagecache.roonlabs.net/im/1/albums/a60032343838353938/cover/512.jpg: statuscode=998 error=Request canceled due to timeout
04/27 11:28:41 Trace: GetImageData[Remote](id=28131 spec=512 key=zppbaaaa uri=https://imagecache.roonlabs.net/im/1/albums/a60032343838353938/cover/512.jpg) => fetched in 100002ms status=998 size=0 overalltime=100002ms
04/27 11:28:41 Warn: [broker/images] unexpected error GET'ing https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030373438323232/photo/4by3_2048.jpg: statuscode=998 error=Request canceled due to timeout
04/27 11:28:41 Trace: GetImageData[Remote](id=39442 spec=4by3_2048 key=ajgcaaaa uri=https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030373438323232/photo/4by3_2048.jpg) => fetched in 100003ms status=998 size=0 overalltime=100003ms
04/27 11:28:41 Warn: [broker/images] unexpected error GET'ing https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030373438323232/avatar/1by1_512.jpg: statuscode=998 error=Request canceled due to timeout
04/27 11:28:41 Trace: GetImageData[Remote](id=39441 spec=1by1_512 key=zigcaaaa uri=https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030373438323232/avatar/1by1_512.jpg) => fetched in 100003ms status=998 size=0 overalltime=100004ms
04/27 11:28:42 Warn: [broker/images] unexpected error GET'ing https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030373935323838/avatar/1by1_256.jpg: statuscode=998 error=Request canceled due to timeout
04/27 11:28:42 Trace: GetImageData[Remote](id=33229 spec=1by1_256 key=bexbaaaa uri=https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030373935323838/avatar/1by1_256.jpg) => fetched in 100003ms status=998 size=0 overalltime=100004ms
04/27 11:28:42 Warn: [broker/images] unexpected error GET'ing https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030313634303530/avatar/1by1_256.jpg: statuscode=998 error=Request canceled due to timeout
04/27 11:28:42 Trace: GetImageData[Remote](id=90649 spec=1by1_256 key=ncefaaaa uri=https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030313634303530/avatar/1by1_256.jpg) => fetched in 100005ms status=998 size=0 overalltime=100005ms
04/27 11:28:42 Warn: [broker/images] unexpected error GET'ing https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030393233383138/avatar/1by1_256.jpg: statuscode=998 error=Request canceled due to timeout
04/27 11:28:42 Trace: GetImageData[Remote](id=149253 spec=1by1_256 key=numiaaaa uri=https://imagecache.roonlabs.net/im/1/artists/7a004d4e30303030393233383138/avatar/1by1_256.jpg) => fetched in 100005ms status=998 size=0 overalltime=100005ms