Which power supply do you have in the 861? I have had an 861v4 and an 861v6 each of which started to exhibit erratic and puzzling symptoms (they still worked but were very unpredictable) and in both cases it was the power supply (the v6 was just under 3 years old). If you can check the 5volt line then do so - it should be set to 5.2v. If you think the power supply is OK then I would reload the firmware and try again.

Cinema/Music: Trinnov Altitude32 8-16,218,Cloud 4 channel, Marantz UD5007,DSP5200SE(2+C),DSP3300(4),DSW(2),271,MShort Ceilings,AppleTV 4K
TV: Marantz SR7013 Wharfedale Diamond 9x4+Celestion(C)
Music: Roon,i7NUC8gen,QNAP TS253A, Sony Scala, MS200, Garrard DDQ650,Wharfedale Diamond 12.3
Kitchen: AD88 (bluetooth via i80).