NAD C-388 w/BluOS2i WiFi Connectivity

I have a NAD C-388 w/BluOS2i (and HDM-2) MDC cards. It has worked very well for several years.
Later, I purchased a Node2i. They are both in my 2-ch music listening/concert watching system. Typically use PC, tablet, or Note phone to control the C-388 using BluOS app to stream AmazonPrimeMusicHD.

Between C-388 and Node2i, I prefer to use the C-388 because it is more direct connection, since the Node2i is connected to Coax1 input of the C-388. However, the C-388 seems to drop the WiFi connection after 5-10 minutes of play. My solution has been to switch to the Node2i - which has always been rock-solid connection.

Investigating this issue, I've found that the Node2i is always connected on 5GHz (never fails), while the C-388 is always connected on 2.5GHz. Home network is all Asus mesh, with AC3100 (master) and three AC1900 (nodes) spread throughout the house and to cover an acre of property (for IEM noise-blocking + tunes while mowing).

Question is about the C-388 WiFi being 'stuck' in 2.5GHz. Seems I need to move it to the more robust 5GHz.

Anyone know if this is possible and how to do that? Is it a C-388 setting or BluOS2i setting? 
@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.
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 had issues with the bluos2i module dropping off the network at random intervals (sometimes even while streaming).  That wifi dongle that comes with the MDC module is complete garbage.  I ended up using a wifi ethernet bridge and using the wired ethernet port on the MDC module.  Has been stable ever since.
Hi, actually I have same issue now, since I recently bought NAD C388 with MDC Bluos 2i but unfortunately the usb wifi adapter was broken now and I was trying to see if I can replace with a new one. I read through your conversation and did some investigation as well. I noticed the original usb wifi is drive support with win7 and Linux (ath9k_htc), would that be possible that usb wifi adapter is like free drive and linux supported. Since I would guess Bluos is based on Linux. I also bought a TP link usb wifi adapter but that needs me to install driver, so I can not use TP link ones at all. 
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 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.
@mwatsme thank you so much, now I am using a wifi bridge with Ethernet output to connect to the MDC 2i for airplay and it works well so far. But I think I will order an replacement USB wifi dongle anyway since I can’t use Bluos app without wifi. Wish you the best. 
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.

Registered an account here just because this thread solved months' worth of frustration. I have the 2i MDC in my C368 primarily for streaming music, and it's been a nightmare getting it to stay linked to my network and to Spotify Connect. NAD's support just reiterates the same "reboot it" then "it's Spotify's fault" every time I've sent in error logs. 


If you're reading this in the future and the Wi-Fi is giving you grief, find any way to get an ethernet cable in your 2i MDC possible. I took an old router and set up a wireless ethernet bridge in 5 minutes, and now it works flawlessly. Most modern WiFi networks are centered around 5GHz, and even when I'd force my phone to get on the same 2.4GHz channel as the 2i's WiFi dongle, I'd would still experience frequent disconnects and drops, or sync issues between what Spotify was supposed to be playing vs. what the MDC was playing. 


I'm not thrilled this $500 product has such a cheap WiFi dongle that doesn't support 5GHz, but after hours of troubleshooting, configuring router settings, and turning receivers and routers off and on dozens of times, save yourself the headache and get a WiFi ethernet bridge if you can't hardwire it directly. 

The main difference will be interface. With a DAC playing a thumb drive, you are at the mercy of that DAC's interface (on-screen vs app-based, remote vs no remote etc.). If you have a huge amount of music, and depending on the thumb drive's folder structure and DAC's interface etc., it may be cludgey to navigate.

With a PC, you use the Application of your choice and can control it in a number of ways... physically manipulating the laptop, wireless keyboard with laptop hooked up to a large screen, or even using a mobile app to control the PC app etc. From a PC you can also access the internet and all streaming services.

I have a dedicated PC in my 2-channel setup and another dedicated PC in my HT setup... it's hard to go back once you're spoiled like this. PCs can do... everything :) And you can get good refurbs for super cheap nowadays.

I'm having insanely frustrating issues with my NAC C368 dropping wifi connection and have been going back and forth with NAD support on this for almost 3 months now with a solution. Before picking up the NAD C368, I was using an older (all analog) NAD amp with a BlueSound Node 2i in the exact same location, and the Node had almost zero issues with staying connected to the wifi. The C368 drops connection all the time. The only conclusion I can come to is that NAD really cheaped out (or just had terrible luck) in picking the wifi connectivity hardware for this, and it's crazy to me that they haven't worked out a solution yet - like, here's a firmware upgrade and a new dongle? Short of a hardwired connection, the best solution I have found has been to use an old Apple Airport Express as a network bridge - I have the Airport Express connected to the wifi network, and then connect it to the NAD C368 with a ethernet cable, and the NAD works just fine. 

I would LOVE to swap in a different USB wifi dongle and have this work as well as the Bluesound Node 2i did. Is there any chance anyone has figured out a way to do this, or sorted out a reason why it's not possible?