Ayre / Aesthetix hum problems?

Bigtee: so I´d better concentrate on Ayre K-5xe or K-1x as I´m very happy with the performance of the V-5xe?
Do you probably know if there are similar problems with CAT SL-1, ModWright SWL 9.0 SE or Hovland ?
Thanks so far for your very kind advise..

I´ve never had a chance to listen to BAT stuff - how is it´s sonic signature and how does BAT differ from Ayre sonic wise?
Btw.: thanks for the great answers so far..

I just have an Ayre K-5xe on loan. Sound is dead neutral, very fast and transparent and tons of detail BUT it lacks slam, body and warmth. So nothing for me..
I´d like to have a pre that combines all ;) So, which is the one to go for.. ARC LS 25 MK II , BAT VK 31 SE, Aesthetix Calypso ?

I just discussed with the german distributor of Aesthetix and they state that Jim White of Aesthetix in his private studio alsways listens with Ayre gear - so he shouldn´t have hum problems at all? Would be interesting to know if this story is true and how Jim solves the "hum problem".
Will insert a Hovland HP-100 P over the weekend - hopefully this is a better match than K-5xe. Nagra PL-L (last weekend) was to cold..

Charles, thanks for your quick reply. As my V-5xe doesn´t include the "M" in the serial no. I´ll send it over sometime to let it be adjusted as soon as I have decided on Aesthetix or something different. It´s realy a pitty that the matching K-5x lacks (to my ears) a bit soundstage depth and warmth (body). Will the "evolution" upgrade solve this "problem" or will you be releasing a K-3xe with these attributes to fill the big price gap between K-5xe and K-1xe?

Charles, thanks a lot for your input, which I highly appreciate! I´ve checked polarity - o.k. All power cords (Electraglide Epiphany) are of the ground. My equippment is resting on Stillpoints and has got rose quarz and Shakti stones on it. The V-5xe is directly connected to a HMS wall socket.
I´ll try to audition a new K-5xe as I want to build a musical pleasing system around the V-5xe and my Ayon Seagull Ceramique speakers.
Does it degrade the sound quality if I would pair eg. the V-5xe with an unbalanced tube pre amp eg. CAT SL-1, ModWright SWL 9.0 SE or First Sound Presence DeLuxe? If so, in which degree?
Whith which tube amps have you/your customers achieved great results?

Just bought a new K-5xe and preferred it in some areas to the Aesthetix Calypso - which is of course a mighty fine product as well. By the way: NO hum problems with Ayre + Aesthetix.