Hi guys. I know the 400 is getting a bit long in the tooth but it still works well and I have not gotten around to identifying a modern day replacement. I recently (not sure why it took 10 years) noticed a problem when two remotes are being used at the same time.
My setup - MSC-400 in the closet with 2 RFX-250s. Serial: Key Digital 8x8 HDMI switch. IR Sources: 2x Fios box, Roku, Nvidia Shield, Vero (kodi). Remotes: 2x MX-980s, 2x MX-900.
The problem is that if I press ANY button on two or more remotes at the EXACT same time that route to the 400 via the RFX-250s, it is ignored. The RFX-250 does light up that it is receiving but the 400 does NOT light up the blue indicator on the front nor does the IR emitter blink.
I have tried various combinations of remotes. I have IR, Serial, and Triggers on the remotes to send to the 400. They all work when sent by themselves but not simultaneously with other remotes.
I have also tried using a second MSC-400 that I have as a backup and the result is the same. I did this is a completely separate location just in case there is some kind of RF interference even though I did not see any indication in any of the RFX-250s.