Perhaps my recent experience will help others who are having problems getting the RC6x Remote to control the VOL key for a Soundbar.
After finding and programming the DirecTV suggested Codes for my Vizio VHT215 Soundbar into a replacement RC66 Remote, I pressed the VOL key and nothing happened... I got an error message that the VOL key was not programmed. I tried several times to enter the Code [two different possible Codes were listed] and had the same non-working result.
I, like many others, thought that the Code must be bad and searched [Googled] the internet for a good DirecTV Remote Code for the VHT215 Soundbar. I spent hours reading internet posts for the VHT215 Code which concluded that a Good Code for the VHT215 was not available. I did not find any posts detailing instructions where someone had successfully programmed the RC6x to work with the VHT215 Soundbar.
I knew that a working Code for the VHT215 exists because the VOL key on my old/broken RC65 was working with my Soundbar. The problem I had was I could not find the working Soundbar Code I had entered [two years ago] into the RC65. After much further internet searching I found an old RC32 Remote Manual which stated that entering the 990 Code into the Remote would display/verify, with blinks/flashes of the Remote's MODE green LEDs, the Code which is currently stored/entered in the DTR, AV1, AV2, or TV MODES of the RC6x Remote. Using the 990 Code I found that the working Code in my old RC65 Remote was 32454... Since I had previously tried, without success, the 32454 Code in my replacement RC66 Remote, I thought that perhaps I had a BAD Remote.
Careful reading of the RC32 Remote Manual revealed that the VOL key is ONLY ACTIVE when the Remote is SET UP for your TV. Since I do not need the Remote to control my TV, I had not entered a TV MODE Code into the new replacement RC66 Remote. I entered the same TV code from my old Remote into my new Remote and ... EUREKA ! The VOL key now works with the Soundbar.
NOW HERE IS How to Program RC65/RC66 Remote Code for Vizio VHT215 Soundbar--
VIZIO VHT215 Soundbar Code: 32454 works for DirecTV RC65/RC66 Remotes.
Note: The VOL key Must Be Activated and ONLY WORKS after a valid TV Code has been entered into the Remote with the MODE switch at top of Remote set to TV position.
IF A TV CODE HAS NOT BEEN ENTERED INTO THE REMOTE, THE VOL KEY WILL NOT WORK WITH THE SOUNDBAR !!!
To Program Remote for the Soundbar [ Turn ON Soundbar ]:
1. Slide the MODE switch at top of Remote to AV1 or AV2 switch position;
2. Press and Hold the MUTE [ round button under VOL ] and SELECT keys at the same time, until Remote's Green LED at the MODE switch blinks/flashes two times; then release both keys;
3. Using the NUMBER keys Enter the 32454 code.
If a Valid Code is entered correctly, the Remote's Green LED at the MODE switch will blink/flash two times.
4. Aim Remote at Soundbar and press the PWR key, under the MODE switch, one time. The Soundbar should turn off; if Soundbar does NOT turn off -- repeat steps 2 to 4.
Code 32454 DOES WORK for the VHT215 and DirecTV RC65/RC66 Remotes.
NOW YOU NEED TO LOCK THE VOL KEY TO THE SOUNDBAR:
5. Slide the MODE switch to the AV1 or AV2 switch position used to program the Soundbar;
Press and Hold the MUTE [ round button under VOL ] and SELECT keys at the same time, until Remote's Green LED at the MODE switch blinks/flashes two times; then release both keys;
Using the NUMBER keys Enter the 993 Code.
If entered correctly, the Remote's Green LED at the MODE switch will blink/flash two times.
8. Press and release the SELECT key. The Green LED at the MODE switch will blink/flash two times.
9. Slide the MODE switch to the Direct TV position [ far left position ].
CONGRATULATIONS !!! If you followed the instructions, the Remote's VOL key will control the VHT215.
Remember, the VOL key is Linked to the TV MODE switch position and MUST BE ACTIVATED by Entering a Valid TV Code before the VOL key Link can be changed and Locked to the Soundbar. After Locking the VOL key to the Soundbar with the 993 Code, the VOL key will control the Soundbar when the MODE switch is in the DirecTV far left MODE position.
If you get an error message saying the VOL key is not programmed, Slide the MODE switch to the TV position and Enter a Valid TV Code Now, or you not be able to Link and use the VOL key to control the Soundbar.
Also Note: These instructions are for a simple system configuration with the Soundbar connected directly to the DirecTV Satellite Receiver Box. These instructions may need to be modified for different setup configurations.