Hello ian !
what do you mean “DTX DL” is a reported bug?
“DTX DL + AMR + SFH” is not a good combination, but “DTX DL + Legacy codecs + SFH” is not a problem. Or at least, nobody reported a bug about this… since it exists for the past 10yrs, I would assume it is stable and not faulty 🙂
Regarding your increase of UL QUAL and DL QUAL HO. It can be due to so many things…
– 1st : SFH settings. Are your MAIO, MA List and HSN well configured within cells from same BTS and between cells from different BTS ?
– 2nd : antenna design. If you have too much overlap between neighbour cells, the Quality will sky-rocket !
– 3rd : HO settings. With activation of hopping, the thresholds for Qual HO are offset by Offset_Hopping_HO (def 1) and QuaL PC is offset by Offset_Hopping_PC (def 0). Ensure those parameters are at default values.
Then you have to go drive test, to see where are the interferences, and what’s hapenning exactly.