Best I can get here on 129 transponder 11 is around 49. Even then you have to hold your mouth just right when tuning. I agree with the others, 17 is pretty bad...
How is it that the CONUS transpoders can be fine but the spotbeams from the same satellite are not? Even if two satellites are approximately co-located, that should make no difference as viewed from a small dish.
He could just happen to be on the edge of a spot beam, or more likely, have a defective LNB. If the OP is truly seeing 129 tp21=52 and tp3=17, that would be my guess, because every transponder/spotbeam comes down from the satellite at a slightly different frequency. His 119 tp21 signal is also low considering that 110/129 are at appropriate CONUS signals as well, and tp21 is the hottest transponder on 119 for most of the country. 119 should always come in fine if the two side satellites are coming in fine, unless you have a multiple dish setup.