NAD C-388 w/BluOS2i WiFi Connectivity

@fuzztone Good call! Firmware was not up-to-date. Seems NAD has been very busy lately. Here are the latest versions (as of 5/15/21)...

• C-388:
  Main= v1.74 (model-specific, NEW)
  VFD= v1.22 (model-specific, not new)
  BT= v1.26 (model-specific, not new)
• BluOS2i: v3.14.10 (updates automatically, not new)
• HDM-2: v1.19 (model-specific, not new)

Apparently, I'll need to work on this a bit.

Didn’t help, but accessing the back of the unit (manual firmware update), was reminded of the WiFi dongle method used for the BluOS2i. Previously, I had dug-out the extension cord that came with the BluOS2i MDC card to improve WiFi reception.
So I was thinking maybe the dongle could be upgraded.
Does anyone know if a standard WiFi dongle can be used?

The USB-WiFi dongle that came with BluOS2i is a Unex DNUA-93F.
https://www.unex.com.tw/products/wi-fi/usb-wifi/802-11n/80211n-usb/detail/dnua-93f
An 802.11 b/g/n, and as I suspected 2.4GHz only.

I’ve ordered a TP-Link Archer T3U Plus and see if it works with BluOS2i MDC card (AmazonPrime Free-Returns if it doesn’t).

As the TP-Link Archer T3U arrived, I was investigating how the NAD C388 was connecting to the Asus mesh router system, again this is made-up of AC3100 (master) and three AC1900 (nodes) spread throughout the house.

What I found while digging into the ’weeds’ of QOS and which device is connected to which mesh node, and watching the traffic analyzer for activity on the C388, which I had just fired-up using BluOS (from my laptop)... C388 began playing like it always does - then abruptly lost connection. Just before that happened, C388 was showing full 2.4GHz signal strength connected to a mesh node just a floor below (although it is a concrete slab and on the other side of a Bedford stone wall).

Just then, the notorious yellow exclamation point showed-up in the Asus control screen. I know what this means... there is a router firmware update available. Asus releases frequent updates, and I’ve had this issue before (several times), when there is a router update ’pending’, the C388 gets glitchy. So approved the Asus router update, which took all of 5 minutes, and now everything is good!

Something about pending router updates the C388 doesn’t like. I had also locked the C388 to the garage mesh node (via Asus router control), that can be good (if you don’t want it floating around amongst mesh nodes) and it could be bad (if the node it’s locked to goes down or gets over-used by other devices). Removed the lock on that, let it roam if it wants. Also enabled automatic scheduled updates on the Asus mesh - see if that helps avoid these issues in the future.

So, ultimately the answer was check if there are pending updates for the wireless router and approve them.

BTW, replacing the supplied Unex DNUA-93F (WiFi dongle that comes with BluOS2i MDC card) with  TP-Link Archer T3U Plus does not work.

I think it has to do with a feature of the Unex DNUA-93F called "Off-load capability".

Has anyone successfully replaced the WiFi dongle that comes with NAD BluOS2i MDC card?

I have moved on to NAD M12, which uses the exact same dongle, and am still using that for wifi connection. Having both C388 and M12 (without built-in amp), I can say that any improvement of sound quality from the 'upgrade' is marginal.
I didn't need the amp section of C388 and wanted the M12 for its features - specifically the digital coax output and XLR in/out - M12 also has bigger, nicer, touch screen.

@parkzhi 
Seems there are three options, listed best -> worst result:

1. Run Ethernet cable to the unit
2. Use a wifi bridge for improved wifi
3. Call NAD/Lenbrook and order a replacement wifi dongle. NAD support is good when you use their website to open a ticket.

I agree it is good to make the unit complete and fully functional - especially if it might be sold or handed down later.
However, as long as the BluOS control device (PC, tablet, cellphone) is on the same network, it should be able to control the BluOS2i MDC card for streaming services and NAS. So if the wifi bridge is on the same network, it should work - although, I haven't tried it.

Also, I had the HDM-2 MDC card installed in C388, and it works great too - now moved to the M12. I use it for watching music videos on YouTube, concerts, Netflix, and Bluray - essentially a 2-ch music/video experience.

The BluOS app also has an Alexa skill available for voice control using Azon Echo devices. "Alexa, ask Bluevoice to...", benefit to doing it this way is the stream isn't bit-reduced by the Echo device; instead, you get full quality/resolution of the streaming service. Have used Tidal this way, before switching to Amazon Music Ultra HD family plan. BluOS MDC supports MQA and does Tidal just fine, but the cost/value/library and ease of use with AzonUHD wins. Pretty wife can listen to country in one room, son can listen to Celtic metal (or whatever that noise is called), while I enjoy my music on the 2-ch system all simultaneously in UHD - which is brilliant. At this point, we have 3 BluOS devices; M12, C388, and a Node2i, which can be easily grouped/ungrouped spontaneously for multi-room/whole-home effect (similar to Sonos/Heos/MusicCast/etc.) all in UHD - and with access to AzonHD personal playlists (my Denon AVR w/HEOS can't do that). My impression is BluOS is a great system with awesome functionality, which adds tremendously to the value of NAD units like C388, M12 and others.