Cannot read property 'toString' of undefined

[mdominoni]

When executing against Bittrex (srsi_macd), since yesterday I receive this error.

zenbot/node_modules/numbro/numbro.js:1111
var parts = x.toString().split('.');
^

TypeError: Cannot read property 'toString' of undefined
at multiplier (/opt/zenbot/node_modules/numbro/numbro.js:1111:22)
at /opt/zenbot/node_modules/numbro/numbro.js:1127:22
at Array.reduce (native)
at correctionFactor (/opt/zenbot/node_modules/numbro/numbro.js:1125:21)
at Object.add (/opt/zenbot/node_modules/numbro/numbro.js:1197:47)
at /opt/zenbot/commands/trade.js:382:78
at /opt/zenbot/lib/engine.js:191:14
at /opt/zenbot/extensions/exchanges/bittrex/exchange.js:113:18
at Request._callback (/opt/zenbot/node_modules/node.bittrex.api/node.bittrex.api.js:112:25)
at self.callback (/opt/zenbot/node_modules/request/request.js:186:22)
at emitOne (events.js:96:13)
at Request.emit (events.js:188:7)
at Request.onRequestError (/opt/zenbot/node_modules/request/request.js:878:8)
at emitOne (events.js:96:13)
at ClientRequest.emit (events.js:188:7)
at TLSSocket.socketErrorListener (_http_client.js:310:9)
at emitOne (events.js:96:13)
at TLSSocket.emit (events.js:188:7)
at emitErrorNT (net.js:1281:8)
at _combinedTickCallback (internal/process/next_tick.js:80:11)
at process._tickCallback (internal/process/next_tick.js:104:9)