Thanks for the info @thomaschan . Are you using the 90R grid resistor? The 5670 is an interesting choice. An Uncle Eric's dumpster tube from VTV (Issue 9 page 10).
Hardware: RPi Zero W | Allo Kali | ProtoDAC TDA1387 X8 | PGA2311 | Icepower 500ASP | Harbeth SHL5
Software: Moode 8.3.3
Source: Win 10 NAS
Software: Moode 8.3.3
Source: Win 10 NAS