Back in June 2017 I ordered myself a pair of Sennheiser PXC550 headphones.
They are supremely comfortable and most importantly, they deliver a wonderfully musical sound [far, far better than anything I’ve tried by Bose, for example]. They have an excellent [really, really excellent] battery life; they are well and robustly made, with good quality materials; they fold away flat for compact storage and they come with a tough travel case that protects them perfectly.
So, I hear you ask, what’s the problem?
Well, they might be a bit stroppy… Let me explain. I use these headphones with 3 pieces of equipment: an iPhone 7, an iPad Pro and a Fiio X5 hi-resolution music player. Both the Sennheisers and the Fiio offer enhanced Bluetooth audio (which almost completely eliminates the clipping you get with default Bluetooth) and the resultant sound quality is mesmerising. Enough to persuade me to invest in quite a lot of high-resolution audio from places such as HD Tracks.
And then, one day, everything fell apart. I’d been listening to an album from the Fiio… The last song finished so I set the phones down and finished the task I was involved with. 30 minutes later, I went back to the headphones but they refused to connect to the Fiio. I tried a link to my iPhone, but that worked. Hmm… iPad? Nope.
Each time I tried to pair the Fiio to the headphones, the player told me that I needed to change the 4-digit numeric pin on the headphones. Except I can’t. They have no keyboard…
For quite a long period of time I just gave up. I used my iPhone. OK, the sound was appreciably degraded – and my investment in 96KHz and 192KHz audio was going to waste, but… I had music.
Then a couple of days ago I spotted that there was a Sennheiser “app” on the Apple App Store. I downloaded it, got it to work and decided it was largely pointless. Except… I found this…
See that bit that is greyed out but which reads, “Set headphones to default settings”?
No, that couldn’t do anything, could it? Well, nothing ventured nothing gained. I hit reset and the first thing I noticed was that a second entry for a pair of PXC550s appeared in the iPhone Bluetooth display. Then I noticed that neither of them worked. Argh!!!
I removed both of these entries, forced the headphones to purge their Bluetooth cache and tried again. Success! Hmm… How about the iPad? Worked first time. Hurrah! Then the Fiio. That, however, failed. Except I got a slightly different error message. I messed about in the settings and found a similar “Reset Bluetooth” option. Tried that, and… it worked.
So all along the problem appears to have been that the Sennheisers, despite being a piece of kit you would not expect to deviate from factory settings, had somehow either scrambled a setting or been modified. I’m not sure which, if either, of these possibilities might explain the reality.
However, I can say [with some relief] that if you experience issues with your Sennheiser Bluetooth headphones and you have access to an iDevice, try a reset via the app.
You might be in luck.