I've been trying both Rioplay and RRR with 48KHz MP2 files and the results seem much better on Rioplay - although you can hear some buzzing / noise artefacts it's definitely usable. On RRR the noise is louder than the source material.
I'm no programmer these days (used to write IBM mainframe assembler many years back) but if you want some sample files I'd be more than happy to send you some to show you what I'm talking about. Did anyone try out the various alternative resampling libraries which were referenced some time back? Is better resampling still seen as a priority?
In hope
Phil