TECHNOLOGY: Battery Drain on wireless mics

[Tempest]

Hey, folks we are all stumped on this one at my current show, and we're all casting out for ideas.

In the show I'm currently working the mic packs are draining batteries SUPER fast.   As in, a fresh battery is put in at half hour, and it's totally dead before intermission.  Erratically.  This has happened on six of the seven packs in use on the show, and at least once goes out EVERY PERFORMANCE; sometimes three or four!  At one point, our engineer put in a fresh battery, saw three bars on the indicator, turned away for a few minutes to do some mixing at sound check, and when she turned back, the low battery indicator was flashing.

We're stumped.  The sound designer, sound engineer, SM and myself have NEVER experienced anything like this before.  We've trouble shot everything we could think of, and are at the point where we're contemplating ridiculous things like whether the brand of condoms we are using is somehow blocking the signal and making them work harder.  Like I said, ridiculous.

So, has anyone had anything like this happen on any of their show, or have any idea of things we can do/check, etc. that is beyond the logical things?

Edit to subject line-Rebbe

[avkid]

What brand and type of batteries are you using?

[NomieRae]

Are they rechargeable batteries? Sometimes those are a little less reliable.

The only thing I can think of is that your wireless receiver is too far away from the transmitters and they're working super hard to maintain a signal - are they kept downstairs/in dressing rooms/etc?  One show I did moving the wireless transmitters to backstage as opposed to the dressing rooms preshow helped quite a bit.

Let us know what you find out!

[iamchristuffin]

Have you tried buying a different box of batteries/a different brand? I once ended up with a dud batch that did the same thing, or simply started out brand new with one bar.

C

[Tempest]

I don't recall what brand of batteries we're using, but they're the same this company always uses, and has not had problems, before.  They are non-rechargeable.  We also thought about the "bad batch" of batteries, but pulled a different box of batteries, from a different order, and it didn't help.

This theatre has the same sound designer/engineer for most of their shows; I'm not sure where he's put the wireless receiver, but I would guess in the same place he always has before.  Could be wrong, of course.  I'll bring that one up as an option.

[nick_tochelli]

How and where are they stored when not in use (not only between performances but also between productions)? If these are house owned mic packs, I'd imagine they are stored together and if they were to get some damage, they could all receive the same damage.

Personally, it sounds to me like the units themselves are faulty and not the batteries. If the packs are drawing all the juice out of the battery at a rapid speed, it might be a short in the pack themselves. And like I said, if they were stored together it stands to reason they would all suffer the same damage. 

[avkid]

One possibility is major interference.
What frequency band are these in?