Here's what I've experienced with my Arcam AVR600 (the model with 3D)...you may find it hard to believe but it's all true.
I'm an extremely patient person but enough is enough. I've had 6 brand new Arcam AVR600's in the last 8 months. One was received DOA but each of the other 5 were installed in my home and they ALL had a tremendous amount of issues not to mention their repeated attempts to blowout my tweeters in my B&W 802D's and HTM2 speakers!! I'm going out of my mind with all the daily problems with EVERY unit I receive!!! Each unit has had the sound delay/sync with video issue, the LOUD POP out the DB1 sub, and of course the LOUD SNAP out the speakers as the Arcam tries to blowout my tweeters when it shuts off during use (and this happens regardless of the volume setting...it even does it when on MUTE) and then immediately powers back on only to do the LOUD SNAP again and repeat the cycle over and over until I physically turn the unit off with the power button on the front of the unit...the remote will not turn the unit off when it's doing this malfunction. On a less frequent basis I'll get 8 - 10 LOUD POPS out the sub rather then just a single LOUD POP out the sub, and at times Ill get LOUD POPS out the 802's also. Whenever mute is activated, the sound is terrible for approximately 3 - 5 seconds when the mute is turned off.
When the unit works properly I do like the sound...it sounds very good IMHO. But even if it had only one of the above, very frequent, daily issues I would not keep the unit. For $6000.00 MSRP it should work flawlessly. Needless to say, this extremely patient person has reached the end of the line with his Arcam AVR600. After 8 months of torment and 6 new units none of which having had any improvement during the 8 month timeframe, it's going back for a refund. Can't say I didn't try to make this work. Sure wish Arcam would have made an attempt to fix their problems cause it does sound very good when it works.