It was quite good again today, at least in the early afternoon and I managed to decode quite a bit of audio. I experimented with using a narrower filter and offsetting the frequency higher so it ignored the data side of things, and it did seem to help.
Modified NRD-525G with Radiokit DRM Decoder Board,
SDRplay RSP-1A, Airspy HF+ Discovery, Dream v2.1.1
Lancashire, UK 53:39.18N 02:10.28W IO83vp